"Gary Sheffield just wanted a chance to prove himself correct. The 40-year-old, nine-time All-Star came to the Mets after being released by the Tigers in April with a chip on his now-healthy shoulder.

"It's something I have always said: When I am healthy I know what I can still do," Sheffield said. "I've seen older players try to convince organizations that they can do this, they can do that and all they get is a 'Yeah, yeah, right.' They never get the opportunity to prove what they are saying.

"This allowed me to prove it," Sheffield said. "Whether people respect that or not, I can live with that now."

While the Mets' season continues its downward spiral, Sheffield returned to the lineup Monday night fighting to show he is still a dangerous hitter. He says he will leave the game when he decides it's time.

"When I was injured I saw the pitches. I knew what to do with them, but when I went to strike them, I couldn't do it," Sheffield said. "Now, I am striking the ball with some authority. It feels good."

Sheffield, who left a game on July 17 with a cramp in his right hamstring, returned from the disabled list on Sunday. He went 0-for-2 as a late-inning pinch hitter and didn't seem happy about it.

"Usually when you come off the DL, you expect to play, but it's been a long process," Sheffield said. "I am just happy that's over and anxious to get out there."

That was not the case when he was released by the Tigers after hitting .225 and limited to 114 games in an injury-plagued 2008. Despite his defiant Motown exit, Sheffield said he felt as if he was walking away from baseball when he left the Detroit spring training complex.

"I shut down my mind," Sheffield said. "I shut down baseball, I told people, 'I don't want to play anymore.' When I got released that was it. It was over.""