"When you have an opportunity to cement a working relationship with a young man like Matt, you definitely have to investigate it and I think both parties are happy that we were able to work it out," general manager Brian Sabean said in a statement. "Obviously, we all saw his immense talent over the last two years, but we all have to remind ourselves that Matt is only 22 years old and his best years are ahead of him."

Cain led rookies with 13 wins and 179 strikeouts last season, going 13-12 with a 4.15 ERA in 190 2-3 innings, finishing in a tie for fourth in NL Rookie of the Year voting. Cain, who also led the Giants in victories.

Cain pitched a one-hitter in the Giants' 6-0 victory over the Oakland Athletics on May 21.

He started last season 1-5 with a 7.04 ERA over his initial seven starts and had his turn in the rotation skipped during a May trip to Houston. He made one relief appearance, then was 12-7 with a 3.34 ERA in his final 24 outings, which included the two innings out of the bullpen.

Sabean heard requests all offseason from teams interested in acquiring Cain, but the Giants were determined to hold onto their talented young pitchers. The Giants selected him 25th overall in the first round of the 2002 amateur draft.