(CBS/AP) OAKLAND, Calif. - Former Cy Young Award winner Bartolo Colon of the Oakland Athletics was suspended for 50 games Wednesday after testing positive for testosterone.

Major League Baseball made the announcement one week after All-Star game MVP Melky Cabrera of the San Francisco Giants was suspended 50 games for a positive test for the same substance.

"I apologize to the fans, to my teammates and to the Oakland A's," Colon said in a statement released by the players' association. "I accept responsibility for my actions and I will serve my suspension as required by the joint drug program."

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He will miss the final 40 games of the regular season and the first 10 games of the postseason if Oakland advances that far. Any remainder of the suspension would be served in a future season, if Colon signs another major league contract.

"It's a shock," Oakland reliever Grant Balfour said. "He's a guy that we're definitely relying on right now. I guess you could say it's bad timing any time, but especially now."

Oakland, which hasn't made the playoffs since 2006, began Wednesday a half-game out in the AL wild-card race. The A's were preparing for an afternoon series finale with the Minnesota Twins at the Coliseum when they got the news from the clubhouse TVs. A closed-door team meeting was quickly called.

"The Oakland Athletics are disappointed to learn of today's suspension," the team said in a statement.

The A's have some decent internal options to replace Colon in the rotation, CBSSports.com's Matt Snyder notes. A.J. Griffin (3-0, 2.42 ERA in eight starts) is scheduled to begin a minor-league rehab assignment Wednesday. Dan Straily (1-0, 3.18 in three starts) was sent back to the minors Tuesday and is also a solid option. Plus, Brett Anderson looked great in his return from Tommy John surgery Tuesday.

The 39-year-old Colon is 10-9 with a 3.43 ERA in 24 starts this season, his first with the A's, and has a 171-122 record in 15 big league seasons. He was due to start Thursday in Tampa.

A two-time All-Star, he won the 2005 AL Cy Young Award after going 21-8 for the Los Angeles Angels.

Colon will lose the remaining $469,945 of his $2 million base salary this year. He also has earned $750,000 in performance bonuses based on starts and $150,000 based on innings, which is not impacted. Thursday's start would have earned him another $250,000, and the suspension will cost him the chance to make $850,000 in additional bonuses based on innings.

Five players have been suspended this year under the big league drug program. San Francisco reliever Guillermo Mota was penalized 100 games in May following his second positive test, and Philadelphia infielder Freddy Galvis and free agent outfielder Marlon Byrd were suspended 50 games each in June.

Colon had been thankful to get a second chance with the A's. His 10 wins are his most since his Cy Young season.

Colon has credited a stem-cell procedure two years ago for saving his career. He had fat and bone marrow stem cells collected and injected into his troublesome right elbow and shoulder in an innovative and unproven technique. Colon had no idea how it would turn out, but he responded and spent 2011 with the Yankees.

Colon signed a $2 million, one-year contract last month to join a rotation that lost two top pitchers this offseason. All-Star left-hander Gio Gonzalez got traded to the Washington Nationals, while Trevor Cahill was dealt to the Arizona Diamondbacks. Closer Andrew Bailey is also gone, sent to Boston in late December.

The Bay Area had already been shocked at the suspension of Cabrera only a week earlier.

"Two guys — that's why they've got the policy, I guess," Balfour said. "The guy may be innocent. You just hope there's some mistake there."

The A's weren't interested in discussing Colon's situation as they try to return to the playoffs for the first time since being swept by the Tigers in four games of the '06 AL championship series. Oakland did welcome back starting left-hander Brett Anderson in Tuesday night's win over the Twins following a 14-month absence because of Tommy John elbow ligament replacement surgery.

"That suspension has nothing to do with me," outfielder Coco Crisp said.