In Tuesday night's Nationals-Rays game, Tampa Bay reliever Joel Peralta was ejected as he came in for the eighth inning after Washington manager Davey Johnson requested that the umpires inspect Peralta's glove. Upon examination, they found a foreign substance, and ejected Peralta from the game while confiscating his glove.
Peralta is a former Nationals reliever, spending time with the team in 2010, and it's widely believed that a former teammate tipped Johnson off to Peralta's glove, which led to the complaint and eventual ejection. The Peralta incident comes a week after Tigers reliever Jose Valverde was accused of throwing spitballs, Also a week ago, former Padres and Blue Jays pitcher (and accomplished author) Dirk Hayhurst blogged about his personal experiences with doctoring baseballs, and how this isn't anything new in the grand scheme of baseball history, or the current game.
In my opinion, I think that whoever the teammate that ratted Peralta out (if someone did indeed rat him out) is a bigger deal than him potentially doctoring balls. As Hayhurst said in his excellent blog post, doctoring balls is a practice has been around since the start of league history, and a former teammate ratting out Peralta seems like it's more of a violation of the unwritten rules of baseball than Peralta's actions.