Seattle ? Seattle Mariners first baseman Richie Sexson, who has missed nine of the last 11 games, has been diagnosed with tendinitis in his left hamstring and likely will be out for another 10 days. Sexson had an MRI on Tuesday, and doctors discovered the cause of the pain and discomfort he has been experiencing in his left leg. The source of the tendinitis is in Sexson’s hamstring, but near his hip at the origin of his hamstring. Trainer Rick Griffin said it’s a rare area for tendinitis to develop, and Sexson was told to do nothing for 10 days.