Between 2009-2010, left-handed San Diego Padres reliever Joe Thatcher posted a 2.14 ERA over 117 appearances, with 100 strikeouts and 25 walks. The situational lefty had established himself as one of several dependable cogs in the Padres' fearsome bullpen. Then, this past spring, he started fighting with some shoulder problems. An MRI revealed no structural damage, but Thatcher has to date been unable to make much progress in a throwing program, and so on Monday, he's set to undergo exploratory surgery.
The operation will knock Thatcher out for at least the next three months, in the event of a simple shoulder clean-up. However, he may need a repaired labrum, and that could keep him out for up to the next calendar year. The surgeons won't know what they're dealing with until they cut Thatcher open and look inside.
Given Thatcher's track record of success, the Padres will hope that he only needs a little sweeping and dusting in the corners, but even that would keep him out for most of the rest of the 2011 season. In the meantime, the Padres will continue to rely on Cory Luebke as the lefty in their bullpen.