OAKLAND -- A depleted A's bullpen will have to do without Andrew Bailey for the remainder of the year, as the club announced Thursday the closer will undergo season-ending surgery on Friday.

The right-hander will undergo a cleanup operation on his sore right elbow administered by Dr. James Andrews, who orchestrated Bailey's Tommy John surgery in college. Bailey said by phone Thursday evening there are a "couple of extra bones floating around" -- symptoms that are not unusual for someone who has been through a Tommy John operation.

The closer mentioned he's only looking at an expected recovery time of six weeks, which will allow him the chance to not only resume throwing sooner, but he can be out of rehab mode by his November wedding to fiance Amanda Scalzo, who will be "taking care of me the rest of the way." Following Friday's surgery in Florida, Bailey plans to start physical therapy in Connecticut.

The news is relatively positive for Bailey, who fortunately learned he has no ligament damage in his elbow. Still, his absence is nothing of the encouraging sort for an A's team that has dealt with a multitude of injuries this year. And, as Bailey noted, "surgery is surgery."

"You never want to have to go through with it," he said. "But it is just a cleanup thing, so I guess it's a best-case scenario. I'm excited there's no structural damage, but I never thought there was because it didn't feel the same way as it did before."

For Bailey, it marks his second time being sidelined, as he missed nearly a month while stationed on the disabled list with a right intercostal strain beginning in late July. The latest injury means the two-time All-Star will not have the chance to match or surpass his save total of 26 garnered in his rookie season last year.

"It stinks," he admitted. "You never want to be hurt. I've been fighting a lot of different things this season, so hopefully this is the last of them. Hopefully, this is what I need to stay healthy for a full season."

In 47 appearances this year, Bailey compiled a 1.47 ERA, currently good for second among American League relievers, along with 25 saves and a 0.96 WHIP.

"He's had a great year," manager Bob Geren said. "We're obviously very proud of what he's done the past two years. He'll be missed the remainder of the season, obviously, but it sounds like good news as far as what he's looking at and what it could have been."

Blevins, Wuertz remain on shelf

OAKLAND -- The A's entered Thursday's four-game series opener against the Rangers looking to hold Texas' magic number at six, but they'll have to do so without relievers Jerry Blevins and Michael Wuertz.

Both relievers were deemed unavailable by manager Bob Geren before the start of Thursday's contest due to bouts with injuries. Blevins is still nursing a strained left shoulder and hasn't thrown in a few days. Wuertz, meanwhile, is battling a sore right thumb but is at least throwing and could potentially return this weekend.

Blevins and Wuertz have combined for 87 1/3 innings this season, and their unavailability will likely mean the club will rely on lefty Craig Breslow in the closer's role for most of the next four days. Breslow has racked up the most innings among all A's relievers, having tallied 69 1/3 innings with 11 games still remaining.

Pennington sits with sore shoulder

OAKLAND -- A sore left shoulder kept Cliff Pennington out of Thursday's starting lineup, but manager Bob Geren said the A's shortstop would be available for defensive purposes.

Swinging the bat is something Geren is hoping Pennington can avoid, but he said he wouldn't be afraid to use Pennington later in the game if necessary. The infielder is 11-for-61 (.180) in September and is now batting .201 over his last 57 games, but Geren said Pennington's shoulder pain is a recent development and had not previously affected him at the plate.

Pennington has played in 145 games this year -- second on the club after Daric Barton, who on Thursday was slated to see action in his 148th contest.

In Pennington's stead, Steve Tolleson got the nod at shortstop, marking his 12th start -- fifth at shortstop -- since being recalled from Triple-A Sacramento on Aug. 13 for his second stint with the club this year. He entered Thursday's contest batting .256 in 18 games.

A's add affiliates in Iowa, Vermont

OAKLAND -- The A's on Thursday announced they have officially added two new Minor League affiliates, as they signed two-year player development contracts with Class A Burlington and short-season Class A Vermont.

The Burlington Bees, stationed in Iowa, will replace longtime A's affiliate Kane County of the Midwest League. The Vermont Lake Monsters, meanwhile, will replace Vancouver of the Northwest League.

"Both areas are steeped in rich baseball history and offer very supportive communities," A's general manager Billy Beane said in a statement. "It should be an exciting and mutually beneficial partnership for all parties involved."

The A's are no strangers to the Burlington Bees, who from 1963-67 were affiliated with the Kansas City A's. That partnership continued even when the A's moved to Oakland in 1968 before coming to an end six years later. Among the more notable players to see playing time with the Bees include Cy Young Award winner Vida Blue and All-Star third baseman Sal Bando.

Worth noting

Ryan Sweeney, who is recovering from season-ending right knee surgery in Iowa, had an MRI on his left knee this week and said via text on Thursday that it "didn't show anything worse." Thus, there has not been a decision on whether he'll have surgery -- which would require four to six months of recovery time -- on that knee as well. ... Kevin Kouzmanoff was back in the A's lineup Thursday after being held out of Wednesday's game just one day after returning from two weeks' worth of nursing a sore lower back. Manager Bob Geren said Wednesday he'd like to alternate Kouzmanoff and Aki Iwamura at third base for the time being, a notion Kouzmanoff said is probably a good one, considering the time he missed. ... Rajai Davis was a late scratch from Thursday's starting lineup due to what the team announced as a "non baseball-related issue." As a result, Matt Carson was moved from right field to center field and Gabe Gross entered the game in right field. ... On Thursday, catcher Kurt Suzuki was presented for the second year in a row with the annual "Good Guy Award" by the local chapter of the Baseball Writers' Association of America. The honor salutes a player who is most cooperative and displays professional behavior with the media throughout the season. ... The A's entered Thursday's contest leading the season series against the Rangers, 8-7. They are 285-291 all-time against Texas. ... Chris Carter's home run on Wednesday marked the club's 95th of the season, which is one more than the lowest single-season total in Oakland history (94 in 1968). Carter received the ball from the fan who caught it in exchange for a bat and signed ball.