New York Yankees pitcher Michael Pineda will start the 2012 season on the disabled list after an MRI exam on Saturday revealed right shoulder tendinitis.

Pineda, acquired from Seattle this offseason in a deal that sent top prospect Jesus Montero to the Mariners, had struggled this spring with velocity. He hit 95-97 miles per hour last season with Seattle, but had mostly been clocked at 91-92 miles per hour this spring.

The 23-year-old Dominican native was vying for a spot in New York's rotation this spring and pitched to an earned run average of 5.68 in six starts. He was tagged for 12 runs on 24 hits and 10 walks in 19 innings, including a disastrous outing on Friday against Philadelphia when he was roughed up for six runs in 2 2/3 innings.

After Friday's performance, the Yankees decided to send Pineda for tests despite the right-hander saying he was feeling just normal soreness.

Pineda was an All-Star during his rookie season in Seattle last year and finished the campaign with a record of 9-10 and a 3.74 ERA in 28 starts.