A's manager Ken Macha on Monday said his ace right-hander won't throw again until Thursday, and when asked if he was mentally prepared to do without Harden for the remainder of the regular season, Macha said, "That's a fair assessment."

Harden, who has been out with a strained right lat muscle since Aug. 19, had to shut down his scheduled 35-pitch bullpen session Sunday.

"Where that places him," Macha said, "is a couple, three steps back."

The earliest Harden could return to action, Macha suggested, would be Sept. 25. What's shaping up as a make-or-break, four-game series with the Angels starts the following day.

"I'm trying to be optimistic," Macha said, "but I'm also trying to lay out a realistic plan."

The plan is essentially the same one Oakland's athletic training staff has been trying to get Harden through for the past three weeks, but it's been derailed at the same point each time.

On Thursday, Harden will play a simple game of catch. If he's pain-free, he'll play long toss and throw from mound distance -- but on flat ground -- Saturday. If everything goes well, he'd throw from halfway up the mound next Monday, then from on top of the mound for full-blown bullpen sessions Wednesday, Sept. 21, and Friday, Sept. 23.

Twice now, Harden hasn't made it past the first bullpen session, sending him back to square one both times.

"Everything would have to go perfect," Macha said. "And I know that everyone's heard that before, and it hasn't gone perfect."

Even if the best-case scenario plays out, there'd only be time for Harden to make two regular-season starts, and he'd likely be on a pitch limit of 70 in his first start back and 80-85 in the second.

"He hasn't pitched in nearly a month as it is," Macha said. "So I think anything we get out of him from here would have to be seen as a bonus."

If Harden can't return to the rotation, Macha intimated, lefty Joe Kennedy will continue to fill in despite the presence of recently promoted Juan Cruz, who dominated as a starter at Triple-A and has been sharp -- one run on three hits and a walk with six strikeouts in six innings -- since being recalled.

"Kennedy's done fine," Macha said. "He's got his pitch count up ... he's done all right."

Kennedy is 1-3 with a 4.37 ERA in four starts with the A's, and 5-11 with a 6.51 ERA in 20 starts overall. He came to Oakland in a trade with Colorado on July 13.

Up and in: It's been a year of dramatic highs and lows for outfielder Hiram Bocachica, who was in the starting lineup for Triple-A Sacramento's home playoff game Sunday night and in the A's starting lineup Monday.

After batting in the ninth inning of the River Cats' game, which went 11 innings and ended Sacramento's season, Bocachica was told by River Cats manager Tony DeFrancesco to get to the airport for a red-eye to Cleveland.

"I said, 'What do you mean?'" said Bocachica, 29. "I couldn't believe it."

Bocachica, a non-roster invitee to Spring Training with Oakland, was batting .444 in 20 Cactus League games when he was hit by a pitch that broke his right wrist. Six weeks later he had surgery to have a piece of bone removed and went home to Puerto Rico.

"I thought I wasn't gonna play at all [this year]," Bocachica admitted.

But after returning to the U.S. on Aug. 26 and going 1-for-12 in four games with the A's affiliate in the Arizona Rookie League, he was sent to Sacramento, where went 4-for-4 with two homers in his first game. He finished the regular season 7-for-17 with six RBIs in four games, then hit .476 (10-for-21) with a home run and four RBIs in five postseason games.

"He was as hot as a firecracker when he came back," said Macha.

Bocachica, who has played in the big leagues for the Dodgers, Tigers and Mariners, was needed in part because the A's are hurting for right-handed power with shortstop Bobby Crosby (fractured ankle) on the DL, outfielder Bobby Kielty (strained oblique muscle) unavailable and outfielder Nick Swisher in a 1-for-28 slide.

"Swisher is struggling," Macha conceded. "I think he needs a couple days off."

Hence, Bocachica's starting assignment nine hours after his plane landed in Cleveland. The Tribe started lefty C.C. Sabathia, against whom Bocachica was 2-for-9 with a homer entering the game.

To clear a spot on the 40-man roster for Bocachica, the A's designated righty Seth Etherton for assignment. The A's also called up righty reliever Jairo Garcia, who was 3-6 with a 4.47 ERA in 44 games for the River Cats this year.

Dribblers: The A's, represented by assistant general manager David Forst, lost three tiebreaker coin flips via conference call Monday, meaning that if they have to play the Angels in a one-game playoff to determine the American League West champion, the game is going to be in Anaheim. If they have to play a one-game playoff for the Wild Card, it will be in Cleveland or New York. ... Kielty isn't cleared to swing a bat, and Crosby is moving gingerly while wearing an air brace on his ankle. ... Jermaine Clark hit a dramatic two-run homer in the bottom of the ninth inning Sunday to send Sacramento's game into extra innings, but Garcia gave up three runs in the 11th on a hit, a hit batter, a walk and his own error to take the loss.

Up next: A's righty Kirk Saarloos (9-7, 4.06 ERA) takes on Indians righty Kevin Millwood (7-11, 3.11 ERA) on Tuesday in the second game of the three-game series at Jacobs Field. The first pitch is scheduled for at 4:05 p.m. PT.