The Yankees are still on top, for now. The Boston Red Sox made some moves this week to bolster their line-up as the Bronx Bombers cling to a half game lead. It was a strong June for the Yankees as we enter the dog days of summer, yet the American League East isn’t secured in any team’s grasp. As for the Yankees (62-42) and the Red Sox (61-42), the pitching rotation is going to be what decides this season. Sure, they both have potent bats behind the plate, but even if you bang in eight runs on the day you won’t pull out a win if your pitchers give up nine (see Boston’s loss to the Oakland Athletics last Tuesday). The Yankees and the Red Sox have, arguably, the best pitching rotations in baseball this season and pitching is, as it always has been, the backbone of the team. Let’s take a look at the aces that will be taking to the mound down the stretch in the last two months of the 2009 regular season.

 The Yankees Starting Rotation:

 C.C. Sabathia

 C.C. Sabathia came over from the Milwaukee Brewers as the big arm the Yankees needed. Sabathia was brought in to solidify the first spot in the rotation after pitching an 11-2 season, ending with a 1.65 ERA. It was anybody’s guess how he perform under the bright lights of New York, but has kept up his part of the bargain with a 10-7 record and a 3.83 ERA. The 161 million dollar man has pitched two complete games of the season, but had a mediocre 3-2 July. In that six-game span he gave up 20 runs, an average of around three a game, which isn’t exactly terrible, but it doesn’t help his 4.00 average ERA. He’s kept this team afloat, but it was really A.J. Burnett, another new Yankee, who’s been the rock of the rotation this season.

 A.J. Burnett

 A.J. Burnett is sitting with a 10-5 record and a 3.89 ERA. This is an even higher ERA than Sabathia’s but the Yankee offense has held him up. He hasn’t lost a game since June 20th, and the Yanks have won every game he’s started through July (on a 3-0 record). Burnett shared the spotlight with Roy Halladay in Toronto with the Blue Jays and had an 18-10 season with a 4.07 ERA (all in all, he’s had a 3.82 ERA through his career), so the Yankees and their astronomical payroll pounced on the chance to get him in pinstripes. His 117 strikeouts leads the Yankees rotation this year and though he lost his first game in August against the (he gave up ten hits in less than five innings and allowed seven earned runs in their 14-4 loss) there’s no reason to think he doesn’t have a chance to match or better last year’s stats.

 Andy Pettitte

 Andy Pettitte has had a less than stellar year (8-6 record, 4.51 ERA), but is still a valuable arm in any situation. In his 15 years in baseball (twelve of those as a Yankee and three as a Houston Astro) he’s accumulated a 223-133 record with a 3.92 ERA, which, by any standards, puts him in consideration for the Hall of Fame. He’s never ended a season with a losing record, and I don’t expect the trend to end this year. Still, he hasn’t won a game since the July 1st, but he’s been eating up innings and has kept the runs in check. If he can limit the damage each game then he’s done his job.

 Joba Chamberlain

 Joba Chamberlain has done his part to put away any worries or confidence issues that have stuck with him since last season. He was a star in the waiting when picked up his contract in 2007 and was placed directly into the bullpen. He was named one of the top pitching prospects in the minors and fans wanted to see the hype take over the game from the start. He pitched amiably in 2008, when he finally saw his chance to start, pitching for a 3-1 record in twelve starts, but he left in early August with an injury to his shoulder. This season he’s sitting with a 6-2 record and a 3.58 ERA and, he’s pitched a .083 ERA in about 22 innings over his recent three game stretch. It looks like he should shape up to be the superstar he was touted to be in 2007.

 The Fifth Spot

 Now, this is the weakness and gap in the Yankees’ starting rotation that will need to be sorted out by the season’s end. There are four solid starters ahead of this position, but it’s never good to be unconfident one-fifth of the time anyway. Chien-Ming Wang was a question mark this season after he was put on the DL last season with a right-foot injury that seems to have followed him into the 2009 season. He was superb through his career thus far (a 55-26 record), but this season he has pitched for a 1-6 record with a 9.64 ERA. He was sent to the DL earlier this season to work on his mechanics, but came back and struggled again. This time he was sent down with a season-ending injury to his right shoulder. In his place, the often-injured Sergio Mitre took his place. Mitre was brought on as a Yankee this year after taking a year off with Tommy John Surgery. He was a big question mark to begin with, and continues to be so with a 1-0 season after three games and a 7.90 ERA. The fifth spot is one of the few Yankee weaknesses this season, but as far as weaknesses go, a spot on the starting rotation is a significant one.

 The Boston Red Sox Starting Rotation:

Josh Beckett

 Josh Beckett has been one of the most prolific pitchers in Boston Red Sox history as he chugs along this season with a 13-4 record and a 3.27 ERA. He recently blanked the Baltimore Orioles in a seven-inning stint in which he allowed only six hits. Beckett is a two-time World Champion (a MVP in the 2003 World Series), and an All-Star. He’s helped lift the curse on the Red Sox and at the age of only 29 he should continue to fill the first spot in the rotation for years if he can remain healthy. Who would have thought that Beckett, who started as a Marlin and couldn’t get a winning season in during his first four season of his career would turn out to be one of the most prominent pitchers in baseball today? The Red Sox have an automatic leg-up with his arm in the rotation.

 Jon Lester

 Jon Lester has had a solid season with a 9-7 record and a 3.90 ERA. He was signed on to a five-year extension with the Boston Red Sox this year and is set to earn another $30 million. There’s no reason not to give this ace what he wants though. Last year he pitched a no-hitter against the Kansas City Royals, making him only the 18th Red Sox to accomplish the feat. He’s been on a roll through June and July, losing only one game in the span and winning three of his six last starts. You can see his ERA dropping slowly as the season progresses, so maybe that’s a sign that he is starting to find his form. It’s a good thing too because after the first two spots in this Red Sox rotation things get a little hairy.

 The Injuries

 The Red Sox have been hurt by injuries to their stronger starters Tim Wakefield (11-3, 4.31 ERA) and Daisuke Matsuzaka (1-5, 8.23 ERA), but have former Atlanta Brave superstar John Smoltz (2-4, 7.12 ERA), Clay Buchholz (1-1, 3.52 ERA), and Brad Penny (7-5, 5.07 ERA). Penny, for his part has been a starter throughout the season, but he’s only won two games since May. Though the Sox have two of the best at the top of the rotation, they’ve been having troubles keeping some consistent starters through three spots in the rotation. Knuckle-baller Wakefield will be Boston’s most valuable asset when he returns from a lower back strain on Tuesday, and it’s just in time as the Yankees are hitting a skid and Boston’s bats are coming alive. With Beckett, Lester, Wakefield, and Penny in the top four slots, the team will be in as comfortable position with their starters as the Yankees.

 It’s really just a matter of time until the AL divisional race really begins to get interesting. To this point, we’ve seen Boston dominate and then hit a slump and the Yankees stutter-start and then explode after the All-Star break. As of now, there seems to be a leveling of the playing field going on between the Red Sox and the Yankees, but the pitching in the end will make or break one of the clubhouses. The competitive edge is with the Yankees, but the Sox are the spoilers and, once healthy, are the team to watch down the stretch. It’ll be another nail-biter come September.