OAKLAND -- On a Monday night when the entire A's bullpen was strong -- pitching eight scoreless innings in the team's eventual 15-inning triumph -- left-hander Jerry Blevins was the "unsung hero," in the words of manager Bob Melvin.

Blevins extended himself by throwing 2 2/3 innings and 35 pitches and escaped a jam in the 14th after allowing the first two Rays to reach base.

In the past, Melvin has referred to Blevins as a "matchup guy," someone he brings in just to face left-handers. And while the lefty has come through in those situations, he's proven himself much more than just a specialist.

In fact, he's thrown almost equally to lefties and righties (22 and 23 innings, respectively) this season, and actually has a lower ERA when facing right-handed hitters (1.96 to 2.45).

Melvin said his reliever has "come a long way," but Blevins insisted he's always felt like he could get any hitter out in any situation, and that he's tried to avoid the lefty specialist role by showing the ability to do more.

"You can pitch yourself into and out of any situation that's provided," Blevins said. "If you pitch well enough, you're going to move yourself up. That's all I strive to do is just get outs, no matter who I'm facing. You do that, they'll see it."

At 45 innings, Blevins is on pace to far surpass his career-high output of 48 2/3 innings from 2010, and he's proven willing and able to throw longer outings when the team needs him to, like Monday.

The A's can thank him for another reason. Blevins' many tweets of pictures of donuts led a fan to bring him a box of the pastries before Monday's game, and when the 15th inning began, he and his teammates began chowing down. The inning ended, of course, with a walk-off.

"Rally donuts," Blevins joked.

McCarthy makes first rehab start at Triple-A

OAKLAND -- Right-hander Brandon McCarthy made his first rehab start on Monday since returning to the 15-day disabled list on June 20 with reccurring right shoulder soreness.

McCarthy gave up six runs on seven hits over 3 2/3 innings for Triple-A Sacramento, but as A's manager Bob Melvin said on Tuesday, it's "more about health than results at this point" for McCarthy, and the starter felt good Tuesday, a positive sign.

After a couple days of rest, McCarthy will throw another bullpen session, and Oakland will then decide whether he makes another rehab appearance or comes right back to the team.

Melvin says there's a "good chance" the righty will make another rehab start, since they'd like him to get back up to 80 pitches -- he threw 66 on Monday night -- but left open the possibility that he won't.

"You want to make sure he's throwing the ball where he wants to and he feels good about himself coming back to the big league level," Melvin said. "We just have not gotten there yet because health is the big issue with him, and once he throws his bullpen, we'll have a better indication."

Another issue involves what to do once McCarthy is healthy enough to return. While the A's will certainly be happy to have him back, they haven't exactly missed him. The emergence of A.J. Griffin and Travis Blackley has helped lead to a 3.73 starters' ERA, good for second in the American League entering Tuesday.

"Tough decisions, yet you can't have too many guys, so we're in a good position as far as that goes," Melvin said. "We'll figure it out once [McCarthy and Brett Anderson] are available and come back to the point where we feel like they're ready to go at the big league level."

The possibility of a six-man rotation seems a relevant one. The added rest would benefit both McCarthy -- perhaps alleviating his shoulder woes -- and the team's three rookie starters, whose innings are under careful watch by the organization.

As of now, both Melvin and Assistant General Manager David Forst said such a move has not been discussed.

Worth noting

• Shortstop Cliff Pennington, on the 15-day disabled list since July 20 with left elbow tendinitis, took batting practice in the cage before Tuesday's game against the Rays. It was the first time he's taken live swings, and Melvin said he could begin a rehab assignment soon.

• Left-hander Brett Anderson allowed two runs in four innings in a rehab start for Triple-A Sacramento on Tuesday, as part of his comeback from Tommy John surgery. Anderson threw 73 pitches.

• Outfielder Coco Crisp remains day-to-day with a left hamstring strain, but Crisp joined Pennington in taking cage batting practice on Tuesday for the first time since injuring himself on Saturday.