RHP R.J. Alvarez was designated for assignment Tuesday by the Cubs. He was claimed off waivers from the Oakland Athletics on June 12 and appeared in 20 games for Double-A Tennessee, going 0-1 with a 7.71 ERA.

RHP R.J. Alvarez was claimed off waivers from Oakland then optioned to Triple-A Iowa. Alvarez had right elbow surgery in March 2016 and then moved his rehab assignment from Class A Stockton to Triple-A Nashville on Thursday.

RHP R.J. Alvarez (right elbow surgery in March 2016) moved his rehab assignment from Class A Stockton to Triple-A Nashville on Thursday, and he threw 1 2/3 scoreless innings. He struck out three without issuing a walk or allowing a hit. Alvarez made two rehab appearances for Stockton, giving up one run in two innings.

RHP R.J. Alvarez (right elbow surgery) will begin a rehab assignment Friday with Class A Stockton, and he will pitch one inning. Alvarez, a reliever, faced hitters for the first time Tuesday, throwing 20 pitches. "I feel really good right now," he said. "It's nice to get those bone chips that were kind of bothering me out of there. I just feel a lot freer." Alvarez has been on the disabled list since March 25.

RHP R.J. Alvarez was transferred from the 15-day disabled list to the 60-day disabled list. He's recovering from March 2016 right elbow surgery.

RHP R.J. Alvarez (right elbow surgery in March 2016) went on the 15-day disabled list retroactive to March 25. The timetable for his return is uncertain.

Alvarez gave up three earned runs on three hits and a walk over an inning's work in Wednesday's 10-3 loss to the Rangers.

Alvarez's struggles at the big league level have been significant. The 24-year-old has pitched to an 11.00 ERA, and after a solo homer to Rougned Odor, has now allowed a staggering seven home runs in 18 innings. Alvarez showed little ability to command his electric stuff at the Triple-A level -- pitching to a 1.51 WHIP -- perhaps leading to his disastrous major league results. Obtaining experience is what's most important for Alvarez, and with Oakland going nowhere, the right-hander is sure to continue making appearances in low leverage situations.

Alvarez was recalled from Triple-A Nashville on Tuesday.

Stuff isn't a question with Alvarez, it's his ability to command it. The 24-year-old struggled in that regard for the most part this season (4.4 BB/9), but he did show some improvement late with Nashville, issuing five free passes in his final 10 appearances. Look for him to work in low-leverage spots until he proves he can be trusted.

Alvarez was optioned to Triple-A Nashville in order to clear a spot for Felix Doubront.

Alvarez's performance in 2015 hasn't exactly been ideal, with 13 earned runs in 9.1 innings. He made just one appearance in his third stint with Oakland, facing two batters and registering a hit and an out. He could see the majors again, but some improvement on his 4.12 ERA at Nashville could help.

Alvarez was recalled from Triple-A Nashville on Tuesday.

The A's jettisoned reliever Tyler Clippard on Monday, which left them with an open spot in the bullpen. Alvarez, who struggled at the big league level earlier this season before being sent back down to the minors, has posted a 4.12 ERA with 33 strikeouts and 12 walks across 24 innings at Triple-A Nashville. He'll add right-handed depth in Oakland's bullpen, likely in a middle-relief role.

Alvarez was optioned to Triple-A Nashville on Friday.

Alvarez's second stint with Oakland lasted less than a week. He was clobbered for five runs on four hits -- including two home runs -- in two appearances during the team's series against the Twins, and was swapped out Friday for Angel Castro. Alvarez throws hard, but he'll need to cut down on the walks and learn to limit the long ball to be an effective major league reliever.

Alvarez was recalled from Triple-A Nashville on Saturday, MLB.com's Jane Lee reports.

Alvarez is an intriguing bullpen arm with some solid pedigree and the ability to miss a good amount of bats. However, Tyler Clippard will remain Oakland's closer until Sean Doolittle is activated from the DL, so saves won't likely be part of the package for Alvarez.

Alvarez was optioned to Triple-A Nashville on Wednesday.

The move comes a day after Alvarez's dreadful outing in which surrendered seven runs (six earned), five hits, and three walks in one inning of work against the Angels. Arnold Leon was recalled to the major league roster in a corresponding move.

Alvarez struck out the side in his one inning of work on Thursday, but also allowed a solo homer to Evan Gattis.

Alvarez, acquired by the A's in the off-season, has been used in low leverage situations out of the A's pen so far this season. He has allowed two home runs in his five innings, but has also shown some promise with nine strikeouts. If Alvarez can keep up the strong K rate, he could find himself appearing in some higher leverage spots as the season progresses.

The Padres traded Alvarez, along with Jesse Hahn, to the A's on Thursday for Derek Norris, Seth Streich and an international signing slot, Jeff Passan of Yahoo! Sports reports.

Part of the package that brought closer Huston Street to Anaheim in July, Alvarez posted a minuscule 1.25 ERA, 0.96 WHIP and 61:13 K:BB in 38 appearances at the Double-A level last season. He wasn't as sharp with his control in a September audition with the Padres, but Alvarez can easily miss bats with his mid-90s fastball, sharp slider and changeup. It should only be a matter of time before he carves out a back-end bullpen role with Oakland.

Alvarez was called up from Double-A San Antonio on Tuesday, MLB.com's Alden Gonzalez reports.

Alvarez spent the season at Double-A between Angels and the Padres after he was traded. He pitched well with both teams, and will receive a chance to audition in September for next year's big league roster.