Yankees fireballer Joba Chamberlain will make his long-awaited debut as a starter on Tuesday. He will be limited to 70 pitches. The entire East Coast media will be drooling.

Pedro Martinez will also make his long-awaited return to the Mets’ rotation Tuesday. Pedro claims that the Mets clubhouse would have been looser if he had been around. Let’s hope he can be awesome and injury free for the rest of the season, because who wouldn’t want to watch just a little bit more acery from one of the most entertaining pitchers of our generation?

No. 1 prospect in America Jay Bruce had 4 more hits on Friday, raising his batting average in his first 4 games to .571. That the Reds not only went out and sign Corey Patterson this winter specifically to block Bruce, but then stuck with him in the leadoff spot, for two whole months, despite his .200 average and his execrable .240 OBP, can only be taken as a searing indictment of Dusty Baker and departed GM Wayne Krivsky, and anyone else in the Reds organization who could have stepped in and put a stop to the madness. Bruce had nothing left to prove in the minor leagues since more than a year ago, and should have been starting in centerfield for the Reds on opening day.

Steeply declining Indians DH Travis Hafner has been put on the DL for generalized suckiness (officially, a “sore shoulder”). Hafner’s bat has fallen off a cliff the last two seasons, beyond what a mere sore shoulder can explain. He may not be truly this bad, but I think it is safe to say that the Indians are going to be regretting signing him to an extension through 2012 for years to come.

Red Sox ace Daisuke Matsuzaka will go on the DL with a strained rotator cuff, missing at least one start if not more. This means an encore performance of the Justin Masterson show. Everyone is talking about how all signs are as good as can be on Matsuzaka’s shoulder, but I don’t know if there can really be “good signs” when we are talking about some sort of rotator cuff problem.

The Carlos Gonzalez era has officially begun in Oakland, where the organization’s top prospect was called up on Friday and quietly got off to a fine 2 for 3 start, amid much less fanfare than that surrounding the callups of Bruce or Clayton Kershaw. I’m not sure if he’s really ready to hit in the Majors - his AAA stats still showed he has some issues with commanding the strike zone - but with Ryan Sweeney going on the DL, the A’s needed someone to play centerfield, and Gonzalez’s plus defense and rocket arm, at least, will play immediately.

Even less fanfare attended the Cardinals’ decision to call up outfielder Joe Mather, and surprisingly, send down Chris Duncan, who hadn’t exactly been sucky. It was already ridiculous how many talented young outfielders the Cardinals have all of a sudden, what with Ducan, and Rick Ankiel, and Skip Schumaker, and Ryan Ludwick, and Brian Barton. You can now add Mather to that list, as he already made a spectacular diving catch in his first game up, and he might have to be on your fantasy radar having already slugged 12 homers and posted a 1.077 OPS so far at Triple-A this season.

Rumors are starting to heat up again about Kenny Lofton possibly catching on with a big league team at last. Despite hitting .296 with 7 homers and 24 stolen bases last season, Lofton has yet to find a taker for his services this year. His defense has declined to the point where he should no longer be an everyday starter, and he can no longer hit left-handed pitching, but he can still put up strong numbers vs. right-handers and should be able to find a place on somebody’s roster as a part-timer. The Cubs and Mets continue to be rumored as destinations, and Lofton would make some sense for both squads. But in my view this is just people stirring up rumors as there has been no credible evidence that either team is willing to sign Lofton. But with lefty stick, ability to hit for average, and still-dangerous speed, it makes no sense that Lofton doesn’t at least have a role as a bench player when people like Mark Sweeney still have major league jobs.

Here is my take on who should be the National League and American League MVPs this year. Unlike Alejandro, I am not trying to guess who will actually be named MVP. Rather, I have tried to decide who actually is the most valuable player in each league. Also, I have offered up my top five picks for each league, because that’s just the generous type of guy I am.

National League

5. Lance Berkman, 1B, Houston Astros
Has anybody been more valuable to the Houston Astros over the past three years? You could make a case for Roger Clemens, but the fact is that if you took Clemens’ bloated salary and actually signed some offensive players, the Astros probably would have won a World Series by now, instead of losing 2-1 whenever Clemens pitches. But the fact is that over the last three years, whenever Berkman is hurt, the Astros lose, and lose horribly, but as soon as Berkman is back in the lineup, the Astros zoom back into contention. This year, Berkman is rather quietly having the best year of his career. He is third in the National League with 126 runs created, and is on pace to set career highs in home runs, RBI, and slugging percentage.

4. Bronson Arroyo, SP, Cinncinati Reds
The Reds surprised everyone by contending for most of the season, and that fact is almost entirely due to the Wayne Krivskey’s brilliant acquisition of Bronson Arroyo for Wily Mo Pena. The Reds have always had tons of offense but have never had any pitching, particularly starting pitching. That is, until Bronson came along and significantly exceeded his career norms to pitch like a Cy Young candidate and give the Reds a legitimate stopper every five days or so. Plus, Bronson quickly became a team leader and showed himself to be an absolute gamer, demanding the ball in the biggest games and volunteering to pitch on three days rest on several occasions. Many people think that the MVP should go to the player who was most valuable to his team, and if that is truly your criterion, it would be very hard not to give the award to Arroyo.

3. Russell Martin, C, Los Angeles Dodgers
A 23-year-old rookie, Russell Martin wasn’t called up from the minor leagues until May, but he has been an absolute godsend to the Dodgers, and I can say with absolute certainty that the Dodgers would not be anywhere near contention now if not for his presence. When Martin was called up, Dodgers catchers had only thrown out one runner in about 30 attempts as teams ran wild on 80-year-old Sandy Alomar Jr., and limp-armed Dioner Navarro. But then Martin came on and has thrown out an amazing 32 percent of basestealers. Martin has also been an oldschool workhorse behind the plate, catching 104 out of 124 games since his callup, and once even catching a Sunday day game immediately after catching all 15 innings of an extra-inning Saturday night game. Despite being a complete rookie who came straight from double-A, Martin has also impressed everyone with his veteran-like leadership behind the dish, once telling Derek Lowe he would not leave the fucking mound until Lowe calmed the fuck down, and drawing rave reviews from no less than the great Greg Maddux himself, who says of Martin, “He has very good baseball sense…If you can’t throw to this guy, you can’t throw to anybody.” But perhaps most importantly of all, Martin has been the only real clutch hitter and leader-type on a team full of introverted types like Nomar, Jeff Kent, and J.D. Drew, serving as the voice of the team to the media despite being a rookie and hitting several huge, David-Ortiz-like late inning homers down the stretch. I don’t think anybody but me will even put Martin on their MVP ballot at all, but the numbers to back it up are astonishing. When Martin catches, the Dodgers are 64-42, 22 games over .500. When anyone else catches, the Dodgers are 16-31, 15 games under .500. Sounds like a pretty damn valuable player to me.

2. Albert Pujols, 1B, St. Louis Cardinals
Every year, the Cardinals get worse and worse, and yet every year they still win the NL Central, because every year Albert Pujols gets better and better. The guy is an absolute beast, leading the entire major leagues in OPS and slugging. Considering the still ascending trendline in his season stats from year to year, it is truly scary to think that we may not even have seeen what King Albert is truly capable of yet. But he was not the most valuable player in the league this year.

1. Ryan Howard, 1B, Phillies
I once said that the only way the Phillies could make the playoffs was if Ryan Howard hit 40 home runs in August and September. Howard has done just about everything he could do except that, and the Phillies, once dead in the water, are now only half a game out of the wild card. Looking at the numbers, Ryan Howard leads the major leagues with 144 runs created this year, and a ridiculous 10.00 runs created per 27 outs. This means that a team of nine Ryan Howards would score 10 runs every game. And while I generally don’t put much stock in traditional statistics, sometimes you just have to gawk at them and let your mouth hang open when you see that Howard is on pace for 61 homers and 149 RBI. As much as I was hoping to have an uncoventional pick for NL MVP, I have to go with the crowd on this one, because, let’s face it, is there any player in the entire National League that you would rather have had on your team this year than Ryan Howard? I think the answer is clear.

American League

5. Travis Hafner, DH, Cleveland Indians
If Travis Hafner hadn’t suffered a season-ending injury that cost him all of September, he would have forced his way into serious contention for the MVP award, despite the fact that the Indians won’t make the postseason. Simply put, when Hafner played this year, he was the most devastating hitter in all of baseball, delivering a staggering 10.31 runs created per 27 outs, puting the NL’s Ryan Howard a distant second among major leaguers with 10.00 RC/27. Even with the injury, Hafner was still a tremendously valuable player for the Indians this year, putting up dazzling numbers of .308/.439/.659 to go along with 46 homers, 100 runs, and 117 RBI - all this in only 5 months of play.

4. Johan Santana, SP, Minnesota Twins
It is clear that Johan Santana is the best pitcher on the planet right now, which makes him a pretty darn valuable player. Although his stellar projected numbers of 19-6, 2.79, and 256 Ks certainly bring him to the fringes of the MVP discussion, they are not quite amazing enough to put him over the top. Whereas someone like Pedro Martinez in 1999 clearly deserved to be MVP (even though he was snubbed), the cult of the 100-pitch-count limit has made it increasingly difficult for a pitcher to put up the kind of truly dominant numbers that could lead to MVP consideration. Still, it’s scary to contemplate what kind of numbers Santana would have put up this year if he hadn’t suffered from a case of WBC disease in April, when he started off the year 0-3 with a 4.81 ERA.

3. Grady Sizemore, CF, Cleveland Indians
Quick, which player is second in the American League to only David Ortiz in runs created this season? You can easily be forgiven if you didn’t know that it was Grady Sizemore before reading this post. Sizemore has had an absolutely amazing season, and is on pace for 136 runs, 55 doubles, 27 home runs, and 75 RBI out of the leadoff spot. Plus, unlike most of the other players on these lists who are first-basemen or DH’s, Sizemore plays one of the all-important “skill positions” up the middle, where he contributes a lot more on the defensive side with his outstanding defense in centerfield. Sizemore has also maximized his value to his team with his durability, playing in every single Indians game so far this season. It is no wonder that the most popular item of apparel among young women this season at Jacobs Field is the jersey that says “Mrs. Sizemore” on the back.

2. David Ortiz, DH, Boston Red Sox
David Ortiz continues to leave the door open to speculation that he is some sort of freakish alien from outer space, as he finishes off a season even more ridiculous than the last two, leading the American League in runs created, breaking the Red Sox record for homers, and getting ever more implausible game-winning clutch hits. I am not sympathetic at all to the contention that the MVP should never go to a DH, especially when one of those DH’s is the guy who made sabermetricians rethink the idea that there is no such thing as clutch hitting. If Ortiz had somehow lifted the Red Sox to the postseason on the sheer force of his will, I think everyone would have conceded the point, but that has not happened, and Ortiz has slumped a bit down the stretch to the point where it once again enters the conversation that he does not contribute any runs prevented on defense, has Manny Ramirez hitting behind him, and plays in a very hitter friendly park.

1. Joe Mauer, C, Minnesota Twins
To truly measure a player’s value, you have to take into account how easy it would be to replace his production with other players. The fact is, far too many first-basemen win MVP awards, because even though first basemen tend to put up huge offensive numbers, they don’t contribute many runs prevented on defense and it is relatively much easier to find another hard-hitting first-baseman than another, oh I don’t know, say, a hard-hitting catcher. Check this out: Joe Mauer as of this writing has created 100 runs for his team. As a catcher. That is an amazing number for any player, but when you consider all the other value Mauer brings to his team as an outstanding catcher, his offense catapults him into MVP territory. We are talking about a catcher who is batting .345 and slugging .500, and is only 23 years old. Basically, we are seeing a young Mike Piazza offensively, only whereas Piazza was a terrible defensive catcher, Mauer not only contributes on defense, but is in fact a dominant defensive catcher, throwing out nearly 40 percent of would-be basestealers and fielding at a .995 clip. So he’s really more like a combination of the best traits of a young Mike Piazza and a young Ivan Rodriguez. Because he puts up a .950 OPS and dazzling defense at a position that is otherwise thought of as an offensive wasteland, or else a tradeoff between offense or defense, Mauer is literally irreplaceable. If you were going to start an expansion team and you could pick any player to build your team around for the future, you would pretty much have to pick Joe Mauer. But he is already the most valuable player in the American League, even now.