I grew up an Atlanta Braves fan and suffered through countless bad seasons. There was an old joke that the Braves were so bad that a guy once left two Braves tickets under the wiper on his car expecting someone to take them. A few hours later he comes out and sees two more Braves tickets with the ones he left.
John Smoltz helped to turn the franchise around and become one of the great pitchers as both a starting pitcher, then relief pitcher and then back to the starting rotation. He had to undergo Tommy John surgery in 2000. As have many pitchers he came back, but I would argue no one had such a successful comeback. In fact, he is the only pitcher in the Hall of Fame to have had Tommy John surgery.
The following clips including Smoltzie talking about this topic.
Dan Patrick interviews Smoltz (go to 12:54 in the clip, although the rest of the interview is pretty fun)