An early peek at top rookies, biggest surpises and worst messes

Orioles lefty Zach Britton is the best of the rookie pitchers playing key roles among teams in the American League East, but if April is any indication, Britton's biggest competition for the AL's Rookie of the Year award is going to come from the Mariners' Michael Pineda. Like Britton, Pineda, 21, wasn't expected to be in the majors so soon. Britton is in the big leagues because of injuries in the Orioles' rotation.Pineda told the Mariners in spring training that he was going to pitch well enough to make the team - and then he did. Pineda is a power pitcher with the chance to be a force at the top of the Mariners' rotation with Felix Hernandez. Pineda is 3-1 with a 2.08 ERA, 1.12 WHIP with 28 strikeouts and seven walks in his first five starts, compared to Britton, who is 4-1 with a 2.08 ERA, a 1.17 WHIP with 19 strikeouts and 12 walks. The other three AL East rookie pitchers to watch: Tampa Bay's Jeremy Hellickson, Toronto's Kyle Drabek and New York's Ivan Nova. * The Nationals' Danny Espinosa and Wilson Ramos each have a chance to emerge among the National League's top rookies. So far, the most productive NL rookie is Cubs second baseman Darwin Barney, who along with Starlin Castro, has sparked the top of the Cubs' order. Barney is like Espinosa in that he's a minorleague shortstop playing second base in the big leagues. * The biggest AL surprise: Cleveland leads the Central, thanks to a strong rotation and bullpen as well as a re-energized bat of Travis Hafner. If the Indians' outfield gets going with the return of Grady Sizemore and more production from Shin-Soo Choo, look out for the Tribe. * Biggest AL mess: The Twins. They are making lots of mistakes and looking listless. Joe Mauer, Delmon Young and Tsuyoshi Nishioka are injured. Alexi Casilla is a bust at shortstop and Francisco Liriano is lost in the rotation. Justin Morneau's stats resemble that of a middle infielder. * Biggest NL surprise: Florida. With Josh Johnson and Anibal Sanchez, the Marlins' flirt with no-hitters on an almost daily basis. Their bullpen is the best in the National League and Omar Infante has helped the defense. If the young lineup continues to develop, they will be around in September. * Biggest NL mess: San Diego. The Padres and Marlins are tied for the lowest ERA in the NL going into the weekend, but the Padres also have the fewest runs scored and the weakest team average. Brad Hawpe, Orlando Hudson and Cameron Maybin, all new players this season, have been disappointments. And Ryan Ludwick, a former Cardinal, is not hitting either. * Best story: Sam Fuld, a fourth outfielder with the Cubs, got a chance in the Rays' lineup when Manny Ramirez retired, and has been sensational with a good average, double-digit steals and incredible catches on defense.