McClellan announced his retirement Thursday, Jenifer Langosch of MLB.com reports.

The right-hander endured nearly a year-long rehabilitation process after undergoing shoulder surgery last November, but his doctor told him simply that he wouldn't be able to pitch at a high level ever again. McClellan posted a 3.79 ERA and 1.28 WHIP over 268 appearances (17 starts) at the major league level, the last of which came with the Rangers in 2013.

Kyle McClellan (shoulders) plans to audition for teams in late June or early July.

McClellan is coming off offseason labrum surgery on both shoulders. It's the second time he's had his pitching shoulder operated on, as he missed big chunks of the 2012 and 2013 campaigns while recovering. McClellan will turn just 30 next month, but he'd have to be considered a long shot at this point to make it back to the majors.

Kyle McClellan has elected free agency.

McClellan had been removed from the Rangers' 40-man roster. The reliever appeared in just seven games at the big league level this season.

Rangers sent RHP Kyle McClellan outright to Double-A Frisco.

McClellan cleared waivers after being designated for assignment earlier this week. The 29-year-old will continue to serve as pitching depth in the minors.

Rangers designated RHP Kyle McClellan for assignment.

McClellan allowed eight earned runs in just 9 1/3 innings of relief with the Rangers, but the 29-year-old right-hander still owns a 3.79 career ERA in the major leagues and could draw some interest on waivers.

Rangers purchased the contract of RHP Kyle McClellan from Triple-A Round Rock.

A lat injury in spring training kept McClellan from having a real shot at an Opening Day roster spot, but he's back in the majors now after posting a 2.00 ERA and 11/3 K/BB ratio over nine Triple-A innings. He'll work in middle relief.

Kyle McClellan (lat) has been activated from Triple-A Round Rock's disabled list.

McClellan will make his debut with the club on Thursday. He's been out since mid-March with a strained lat but could eventually be an option for the Rangers' bullpen.

Kyle McClellan (lat) has been throwing off a mound in extended spring training.

It's good to know, but there's no timetable for when McClellan might be ready to appear in games. He's been dealing with a strained right lat since mid-March.

Kyle McClellan (lat) is expected to throw off a mound by May 1.

McClellan, who joined the Rangers on a minor league deal this winter, has been sidelined since the middle of March with a strained right lat muscle. The 26-year-old right-hander could be an option for the starting rotation or the bullpen if he can avoid setbacks.

Kyle McClellan (lat) will not use the opt-out clause in his minor league contract with the Rangers.

McClellan could have become a free agent if he didn't make the Opening Day roster, but he will remain with the organization while rehabbing a strained right lat muscle. The 28-year-old right-hander could need as much as 6-8 weeks before he pitches in a game.

Kyle McClellan has been diagnosed with a strained right lat muscle.

The recovery period for such an injury is typically around 3-4 weeks, according to Fort Worth Star-Telegram reporter Jeff Wilson. It's a costly setback for the 28-year-old right-hander, whose Cactus League debut was delayed with right shoulder soreness. McClellan was hopeful he could win a spot in the Rangers rotation heading into spring, but this injury all-but-guarantees he starts the season on the disabled list.

Kyle McClellan (shoulder) tossed two scoreless innings Tuesday in his Cactus League debut with the Rangers.

McClellan is over the shoulder soreness that plagued him earlier this spring. The Rangers haven't decided yet how they plan to use him this season. He has served as both a starter and reliever in his big league career.

Kyle McClellan (shoulder) will likely make his Cactus League debut against the Brewers Tuesday.

Soreness in his right shoulder has kept McClellan out of action thus far this spring. McClellan has been used as both a starter and reliever in his career, but the missed time will likely relegate McClellan to a bullpen role in Texas if he's able to make the team.

Kyle McClellan (back) could make his Cactus League debut next week.

McClellan, who has been slowed with a sore back this spring, threw a 35-pitch bullpen session on Sunday and ramped things up to 50 pitches on Wednesday. He's scheduled to throw a live batting practice session on Saturday, which could be the final hurdle before game action. McClellan is still hopeful that he could be a factor in the fifth starter race, but it's more likely that the Rangers see him as a longman right now.

Kyle McClellan (back) threw a successful 35-pitch bullpen session Sunday.

"I felt great," McClellan said. "I started out nice and easy at 80 percent and, once I got through, I was letting it go 100 percent with no pain. So very encouraging." McClellan is a couple weeks behind but thinks he can still get stretched out enough to compete for the No. 5 spot in the rotation. Realistically, though, he'd be happy to land a gig as a long man in the bullpen.

Kyle McClellan (back) will throw off a half-mound Friday and could be ready for a bullpen session as early as Sunday.

McClellan has been nursing a sore back since the beginning of camp. As long as he can avoid a setback, he has time to make his case for a spot in the Opening Day bullpen.

Kyle McClellan (back) was not able to throw his scheduled bullpen session Sunday.

McClellan is still nursing a sore back. "Frustrating," McClellan said. "It's going to take time. It's disappointing games have started and you're not in them. But we've got a lot of time. If it's still an issue in two or three weeks, I'll be concerned." The back ailment isn't a big concern, but it doesn't help McClellan's chances at earning an Opening Day bullpen spot.

Kyle McClellan (shoulder) is scheduled to throw a bullpen session Sunday.

McClellan is six months removed from season-ending shoulder surgery and has been shut down since last week due "general soreness." The 28-year-old right-hander will need to be healthy if he has any chance of winning a spot on the Rangers' Opening Day roster, but said he expects to be game-ready by early March.

Kyle McClellan (shoulder) said he's thrown "16-17" bullpen sessions this offseason, with six of them at maximum effort.

McClellan was limited to just 18 2/3 innings last season prior to undergoing shoulder surgery, but he's all systems go at the beginning of spring training. The Rangers will give him a chance to win a rotation spot, but his best shot at making the Opening Day roster is likely as a long man.

Rangers signed RHP Kyle McClellan to a minor league contract with a spring training invite.

McClellan was limited to just 18 2/3 innings last season prior to undergoing shoulder surgery, but he's already throwing bullpen sessions. With a 3.69 ERA over 378 innings in the majors, the 28-year-old right-hander should have a good chance to win a job as a swingman if healthy.