Sean Doolittle was back Tuesday – back with the River Cats, the team he played for in 2009 when he first blew out his left knee, and before he reinvented himself.

Then, Doolittle was a first baseman and outfielder who hit 22 home runs in the minors in 2008. Tuesday night, he jogged in from the bullpen, 25 years old and making his first Triple-A appearance as a hard-throwing relief pitcher.

Doolittle struck out four of the seven Fresno Grizzlies he faced, his fastball regularly clocking at 95 mph. In 23 minor league innings this season, the left-hander, who before last fall hadn't pitched competitively since college, has struck out 44 batters and allowed eight hits.

"It's a little bit surreal," Doolittle said. "(Tuesday night, manager Darren Bush) shook my hand, I was done, and I sat there on the bench. I sat there, and I was like, I can't believe I'm back here."

A pitcher and position player in college at Virginia, Doolittle left as the program's career leader in wins and RBIs. The A's drafted him 41st overall in 2007 as a position player.

"He could hit," said Bush, who managed Doolittle at Class-A Stockton in 2008. "And he could pick it at first."

In 2009, Doolittle played 28 games with the River Cats before tearing his patellar tendon while making a throw from right field. He later reinjured the knee and, while finishing rehab from his second knee surgery last spring, injured his right wrist on a swing.

The A's, Doolittle said, gave him the choice of recovering at home, his right wrist in a cast, or staying at the team's spring training facility in Phoenix and doing pitching work.

"I thought, mentally, it'd be way better for me to do that than go home and just sit there," he said. "So that's essentially how it started."

He played long toss for a month, building up strength in his left arm.

Meanwhile, the injured wrist "just wasn't progressing." In August, he said, doctors suggested he take the offseason off to let the wrist recover.

If it continued to bother him when he started taking game swings again, they said, he could face surgery with six to eight months recovery time.

"Once the doctors told me that, I called (A's director of player development Keith Lieppman) and said, 'I can't do this anymore,' " Doolittle recalled. " 'I can't be hurt anymore. I can't have this hanging over my head this offseason.

" 'Before I'm totally at the end of my rope with this game, I want to switch and try to reignite that fire. Have some fun with it before I go out.' "

At that point, Doolittle said, he had thrown in simulated games and live batting practice. He pitched on the last day of the rookie ball season last fall. He started this season in Stockton, where he struck out 21 hitters in 10 1/3 innings. Promoted to Double-A Midland, he gave up two hits and one earned run in 11 innings, striking out 19.

Doolittle said he did not throw this hard in college, where his fastball hit 88 to 92 mph and touched 94. But he now weighs a solid 210 pounds, and as a reliever knows he will throw limited innings, "so I can let it go a lot more."

Plus, his body is well-rested.

"Being left-handed and able to throw low-to-mid-90s with that command is something special," said River Cats pitching coach Scott Emerson. "Now we've just got to take a look at the secondary pitches and see how advanced he is.

"This is going to be a challenge for him. He hasn't faced these type of hitters, and we'll see how that breaking ball and stuff plays out."

Regarding the possibility of another promotion, Doolittle said: "I just know it's a possibility. If it happens next week, in September, if it doesn't happen until next year, you won't ever hear me complain.

"In Midland, in the Texas League, the bus rides are really bad," Doolittle said. "When I was there, we had a 12-hour bus ride to Northwest Arkansas, and all the guys on the bus were complaining about it. And I'm sitting there and I'm like, 'This is awesome.'

"I don't want it to sound cliché, like I'm just happy to be here. But, essentially, I am."

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