By Larry Fine

Pettitte, not blessed with an overpowering fastball or trick pitch, won five World Series rings with the Yankees and amassed a major league record 19 post-season wins on the strength of his poise, determination and heart.

The broad-shouldered left-hander pitched big games with an unshaven stubble, cap pulled down just over large dark eyes to stare down batters with his glove held high against his face.

Grit and guts helped the soft-spoken Texan by way of Louisiana compile a career record of 240-138, including three seasons with his hometown Houston Astros.

Last year he was 11-3 with a 3.28 ERA despite spending two months on the disabled list with a groin injury.

Pettitte, with his wife Laura at his side, said he had contemplated retirement the last two years but stayed on.

He said he believed it was time to quit after the Yankees were eliminated in the playoffs by the Texas Rangers last year, one step away from another World Series. The Yankees, hoping he might reconsider, told him to take his time before deciding.

When New York failed to sign free agent Cliff Lee, who accepted an offer from the Philadelphia Phillies, Pettitte said he felt "tremendous (personal) pressure" to return and started working to see if he still had the urge to compete.

"When they didn't get him (Lee) I felt a huge obligation," Pettitte said. "I felt like I owed it to the team. I knew they would probably need me."

He said he reached a final decision early this week.

"The thought of packing my bags again and leaving just didn't feel right in my stomach," said Pettitte, whose immediate plans revolve around spending time with his family.

Pettitte denied speculation his decision was affected by the burden of expectations he will be called as a witness this summer in the trial of former team mate Roger Clemens, charged with lying to a congressional committee when he denied using performance-enhancing drugs.

"That has not had any effect, zero," Pettitte said about his retirement. "I would never let that interfere with a life decision I was going to make for me and my family."

Pettitte has admitted using human growth hormone to help him overcome injury and said Clemens told him he had used HGH.

Despite his admission, Pettitte said he was always treated well by fans across baseball. "I've tried to handle things the way I thought that I should. I try to be genuine."

Pettitte became the first member of the Yankees' so-called "Core of Four", comprised of shortstop Derek Jeter, catcher Jorge Posada and closer Mariano Rivera, to retire.

"I'm really gonna miss them. Looking back there and seeing Jeet, and Sado and looking out at that bullpen and knowing that you've got Mariano coming in and closing out the game for you," he said. "Those guys are huge reasons I've been able to be as successful as I have. Special players and special friends."

(Reporting by Larry Fine, Editing by Frank Pingue)