Michael Pineda Will Not Make Yankees' Rotation Five-Headed Monster,  Lands on Season-Ending DLCredit this American League East assist to the Seattle Mariners.

Michael Pineda, the 22-year-old pitching phenom who was sent from Seattle to New York in the offseason for bit parts and star hitting prospect Jesus Montero, will miss the entire 2012 season, Yankees general manager Brian Cashman told reporters Wednesday afternoon.

Pineda has a labrum tear in his right shoulder — his pitching arm. He'll have surgery Tuesday.

Pineda had battled tendonitis and other soreness near the end of spring training, which led to him being held out of the start of the big league season. But the labrum tear did not happen until a recent rehabilitation start, Yankees management said.

Pineda had also been battling velocity problems throughout the spring, although he had guaranteed that his pitch speed would go up as he got closer to making major league starts. But the tendonitis — and now the labrum tear — have put off those hopes for another season.

The Yankees' rotation is still well-stocked, from ace CC Sabathia to young star Ivan Nova. Hiroki Kuroda has been more than capable for New York this season, but Phil Hughes and Freddy Garcia have both had trouble in their early starts.

New York was resting easy, knowing that if Hughes and Garcia couldn't perform, Pineda and the recently unretired Andy Pettitte would be there to take their place. That strategy is now considerably weaker.

Pineda is considered a rising pitching star in Major League Baseball. He went 9-10 with a 3.74 ERA in 28 games (171 innings) for the Mariners in 2011, but his statistics suffered from his playing with a weak offense behind him. New York fans have been salivating for his arrival since the trade was announced, especially after the Yankees' pitching holes let the team down in its World Series defense in 2010 and again last year.

The Yankees gave up their best hitting prospect in years — Montero — for Pineda, and Cashman said he was "devastated" by the news on Wednesday afternoon. But he emphasized that Pineda’s injury was recent and in no way reflects the trade with the Mariners.

Still, Red Sox fans have to appreciate the karma Seattle has produced in the American League East.