Most baseball teams have one. Do you know him. He’s that starting pitcher who’s tagged the “staff ace,” the guy who dominates the opposition, snuffs out losing streaks, and is hands-down the best pitcher in a team’s starting rotation. In fantasy baseball, these pitchers are gold, and their names carry a lot of weight on the draft table and in trade negotiations. However, the big names don’t always hold up and are often relegated to the role of ‘second banana’ in a team’s rotation. The key in fantasy baseball is identifying who has lost a spot and who has stepped into the role of ‘ace’. A big name down a notch can help you get something in a trade and catching the newfound ace will help you win your league. Here are some teams currently going through a trade at the top of their starting rotations:

San Francisco-

For the past few seasons, there has been no question about the fact that Tim Lincecum has been the ace of the Giants’ rotation. His numbers have been among the upper echelon of starters in either league and his value in fantasy has been unquestionable. However, in 2012, Lincecum has struggled big and been forced out of the ace role for not one, but two other starting pitchers. Madison Bumgarner is a pitcher on the rise. The lefty has continued to improve and is making a name for himself among the best young left-handed pitchers in the game. Matt Cain’s recent perfect game, combined with his impressive numbers, make him a threat to unseat Lincecum as well.

toronto-

Although there were discussions about his status as a true ‘number 1’, it was widely held that Ricky Romero was the de facto ace of the Blue Jays staff. The inconsistency and poor peripheral stats have been somewhat masked by a decent win total. Although Romero had a decent second half last year, Brandon Morrow is increasingly seen as the best pitcher in this group.

Oakland –

The A’s traded most of their service arms in the offseason, leaving Brandon McCarthy as the ace of Oakland’s rotation. Preseason hype from various publications trumpeted the fact that McCarthy was ready to take the next step as a number one starter. Although he has pitched well, injuries and a lack of strikeouts have kept McCarthy from taking the next step forward. Jarrod Parker, on the other hand, has started to make a name for himself with some great outings and is priced much cheaper for fantasy owners. Although the ‘ace’ tag for a team like the A’s hardly conjures thoughts of dominance, there is fantasy value here.

miami-

While he’s been healthy (which hasn’t been often enough of late), Josh Johnson has been the ace of the Marlins’ staff. This year he has stayed healthy but has barely pitched like him. Opponents are hitting over 100 more points against him and his ERA is about 3 times higher than it was in 2011. The pitcher who has become one of the best on the staff is newcomer Mark Buerhle. His material is nowhere near Johnson’s level, but you can’t argue with the results. His ERA and his WHIP are notably better than Johnson’s and he has allowed half as many free passes.

Arizona-

After a 21-win season in 2011, it could be argued that Ian Kennedy is the ace of the staff, but Daniel Hudson is the young arm the Diamondbacks are looking for to lead this team. Instead of improving, his numbers have steadily declined since a midseason trade landed him in the desert in 2010. Fantasy owners know Wade Miley is the young arm (he’s only 25) raising the stats in Arizona. until now. this year. He may have seemingly come out of nowhere, but Miley is making his mark in the D-Backs’ rotation and has been the top fantasy pick so far in 2012.

Try not to be fooled by the big names. Pitchers who are supposed to be the “aces” of their staff don’t always deliver with spades.