Braden's long road back is extended again. (Getty Images)

A's starting pitcher Dallas Braden will be forced to undergo another surgery on his throwing shoulder, Athletics manager Bob Melvin told reporters Tuesday. Melvin called the surgery "exploratory," and said it's necessary because the shoulder hasn't responded to the first surgery as hoped (via Susan Slusser).

This is pretty bad news for Braden's long-term prospects. Braden first had the surgery well over a year ago. In the spring, it was expected that he'd be back at some point this season. No timetable has yet been given for his return, but this season is surely out of the question.

Braden, 29, isn't eligible for free agency until after the 2013 season.

Braden was only able to make three starts in 2011 before the injury ended his season. In 2010, his only full season, Braden was 11-14 with a 3.50 ERA, 1.16 WHIP, five complete games, two shutouts and 113 strikeouts in 192 2/3 innings. He's best known for throwing a perfect game on May 9, 2010 and for a spat with Alex Rodriguez when Braden was angry that A-Rod walked over the pitcher's mound in Oakland.

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