Pettitte, a 38-year-old left-handed starter, suggested last fall after the New York Yankees lost to the Texas Rangers in the American League Championship Series that he may not return in 2011 for a 17th major-league season.
"When I left Arlington Stadium last year, I felt like I was done," Pettitte said Friday during a news conference at Yankee Stadium. "I just felt like I should make sure.
"My arm feels great, my body feels great. I've been working out extremely hard the past three weeks. My heart's not where it needs to be. My heart is not fully sold out to do this again."
Pettitte made his major-league debut in 1995 with the Yankees and went on to pitch a total of 13 seasons with New York, playing for Houston from 2004-06.
He finished with a 240-138 record and 3.88 earned run average. Pettitte was selected for all-star teams in 1996, 2001 and 2010 and was a member of Yankees teams that won World Series titles in 1996, 1998-2000 and 2009.
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