Cook was traded from the Athletics to the Red Sox on Friday, the Boston Herald reports.

Manager John Farrell indicated that Cook, who was in Triple-A, will serve in middle relief for the Red Sox when he joins the team. The 28-year-old had back-to-back dominant seasons with the Athletics in 2012 and 2013, but has been less than stellar each of the past two seasons. Perhaps a change of scenery will provide Cook with what he needs to be an effective option out of the bullpen once again.

Cook was optioned to Triple-A Nashville on Sunday, MLB.com's Jane Lee reports.

Cook simply wasn't getting it done in the big leagues this season, allowing a run in all but one appearance on his way to accumulating a 10.38 ERA. He'll get a chance to work it out in the minors, where the right-hander will need to show some consistency before receiving another opportunity.

Cook took the loss on Wednesday night, allowing three runs over 0.1 innings.

Cook struggled in the spring and was sent to Triple-A, but seemed to have worked his issues out and was used in a tie game on Wednesday. The A's will likely consider the outing just a blip on the radar, but will watch him closely after his issues this spring.

Cook made his return to the A's on Sunday, throwing a scoreless seventh inning in a tie game.

The A's threw Cook right into a high leverage spot as he entered the game in a 5-5 tie. Cook has a chance to return to the setup role he has manned the last couple of years with a few strong outings, especially with the A's struggles so far in the bullpen.

Cook was recalled from Triple-A Nashville on Sunday, CSN Bay Area reports.

The Athletics decided to ship Kendall Graveman back to the minors in a corresponding move, opening the door for Jesse Chavez to earn a full-time rotation spot while Cook helps restore some bullpen depth. Cook has been one of the A's top relievers since making the squad out of spring training as a rookie in 2012, but his unexpected struggles in spring training resulted in him opening 2015 with the Triple-A club. He since seems to have ironed out his issues, as he tossed 5.2 scoreless innings for Nashville while conceding only one hit and walking two batters.

Cook was optioned to Triple-A Nashville on Tuesday, Jane Lee of MLB.com reports.

Cook struggled mightily in five appearances with the major league team this spring, giving up a whopping 13 runs (10 earned) on 16 hits in 5.1 innings. The team will send him down to work on some mechanical adjustments, but it sounds like Cook could return in short order if he's able to get things ironed out. On the bright side, he did issue just one walk in Cactus League action.

Cook isn't considered a lock to break camp as a member of the bullpen for the Athletics, Susan Slusser of the San Francisco Chronicle reports.

After delivering stellar numbers in middle relief for the Athletics over the last three seasons, Cook was once viewed as a potential candidate to close at the beginning of 2015 with Sean Doolittle (shoulder) likely to open the year on the DL. Instead, a horrendous spring training during which he's surrendered 13 runs (10 earned) on 16 hits over 5.1 innings has put his standing on the 25-man roster in peril. Unlike some of the other competitors for the remaining bullpen spots, Cook has minor-league options remaining, which further hurts his chances of coming away with a gig. He'll need to turn the corner over the next two weeks of Cactus League play if he hopes to avoid heading back to Triple-A for the first time since 2011.

Cook will be in the A's closer competition this spring due to Sean Doolittle likely opening the year on the DL, reports Jane Lee of MLB.com.

Tyler Clippard is likely the favorite for saves, but Cook did serve as the A's closer for a half in 2012 and is coming off an excellent 2014 where he struck out a batter per inning and had a 1.08 WHIP. Cook's walks (4.0 BB/9 in 2014) are the biggest issue with him closing, but he did improve his control in the second half in 2014 with only 6 walks in 22.2 innings after the All Star Break.

Cook agreed to a one-year, $1.4 million contract with the Athletics on Friday, Jane Lee of MLB.com reports.

Cook pitched a solid 2014 campaign with the A's in 2014, finishing with a 3.42 ERA and 1.08 WHIP with 50 strikeouts over 50 innings. However, he also walked 22 over the same timeframe, an issue he will have to correct. He sports a mid-90s fastball, but figures to serve more in middle relief for the club in 2015.

Cook came on in a save opportunity on Sunday and was terrible, allowing three walks while only retiring one hitter.

Cook filled in for Eric O'Flaherty who was nursing a sore back and failed badly. He walked the first guy he faced on four pitches, retired Jon Singleton and then walks two more guys before getting yanked. If the A's need a fill-in closer any time soon, it will not likely be Cook they turn to.

Cook threw a scoreless 10th inning with two strikeouts and earned the win on Monday night.

Cook has not given up a run since June 22 and has now thrown 16.2 consecutive scoreless innings. He lowered his ERA on the season to 2.48 and looks to be totally back to his dominant form of the past. He is a sneaky add in deeper leagues if teams are looking for ratio help and if Sean Doolittle were to falter of get hurt, Cook could have a shot to slide into some save opportunities.

Ryan Cook got his first save of the season, recording four outs in Sunday's win over the Marlins.

Sean Doolittle was unavailable, having pitched two days in a row and blowing the save on Saturday. Cook entered with two outs in the eighth inning, getting Giancarlo Stanton to ground out to end the inning. He then enjoyed a tidy 1-2-3 ninth inning. Cook sports a 3.91 ERA, a 1.48 WHIP, and a 25/15 K/BB ratio. Barring a rash of injuries, Cook is unlikely to get more than one or two more save chances the rest of the way.

Athletics activated RHP Ryan Cook from the 15-day disabled list.

As expected. Cook has been out for about a month with a right forearm strain, but he had no issues during a rehab game on Saturday. He'll return to a 2.92 ERA and 15/9 K/BB ratio over 12 1/3 innings.

Ryan Cook (forearm) is expected to be activated from the disabled list Tuesday.

Athletics manager Bob Melvin said so during an appearance on MLB Network Radio on Sirius XM on Tuesday morning. Cook has been out for about a month with a right forearm strain, but he made it through a minor league rehab appearance on Saturday without incident.

Ryan Cook (forearm) is aiming to begin a minor league rehab assignment on Saturday.

Cook threw another bullpen session on Thursday morning and reported feeling great. He is on track to return to the A's bullpen early next week. The right-handed setup man has been out since May 8 with a forearm strain.

Ryan Cook (forearm) threw all of his pitches during a 20-pitch bullpen session Tuesday.

Cook felt great and will throw another 'pen session Thursday. It's not clear what the next step is after that, but a simulated game or two and then a rehab assignment is likely. If all goes well, he could be back in the A's bullpen pretty soon.

Ryan Cook (forearm) has been cleared to throw.

Cook will start out with light games of catch before eventually advancing to bullpen sessions and then simulated games. The right-hander has been on the disabled list since May 8 with a right forearm strain. If all goes well, he could be back in early June.

Athletics manager Bob Melvin said Tuesday that Ryan Cook (forearm) "feels really good."

Cook hasn't resumed throwing yet, but he's responded well to exercises. "When you hear forearm, you can't help but think Tommy John, but we certainly don't expect that to be the case, and I know he's kind of champing at the bit to get going," Melvin said.

Athletics placed RHP Ryan Cook on the 15-day disabled list, retroactive to May 8, with a right forearm strain.

The results of the MRI on Cook's forearm aren't yet known, but obviously the injury is bad enough that he's going to need at least a couple weeks of down time. It's his second trip to the DL, as he dealt with shoulder issues at the beginning of the season.

Ryan Cook will have an MRI taken of his strained right forearm.

Cook sustained the injury during the first game of the Athletics' doubleheader with the Mariners on Wednesday. For his part, Cook said he's "really optimistic" the injury isn't serious. More should be known Thursday.