Four-time World Series champion Javier Lopez announces his retirement

Reliever Javier Lopez, a Rule 5 pick who went on to win four World Series championship rings with the Red Sox and Giants, is retiring.

Lopez, 39, was a free agent.

"More than anything, it's just time," Lopez said. "It's a young man's game. Although I think I can compete, it's getting harder and harder to get ready for spring.

"I'm looking forward to some other things in my life. We'll see what they are. I don't know yet, but we'll come up with something."

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Lopez did not make his major-league debut until he was 25, but wound up pitching for 14 seasons, finishing with 839 appearances, 41st on the all-time list.

Originally selected by the Diamondbacks in the fourth round of the 1998 draft, he went to the Red Sox as a Rule 5 pick in 2002.

He won his first World Series with the Sox in '07, but made his biggest mark with the Giants, contributing to their championship bullpens in 2010, '12 and '14.

"I've been representing players for over 30 years, and this is one of the finest human beings I've ever represented," said Lopez's agent, Barry Meister.

"He's someone I look up to, not just as a player, but as a man. I love this guy."