Smith was traded to the Mariners on Monday, Jon Heyman of CBS Sports reports.

EDGE Analysis

Smith was part of a deal that also sent Roenis Elias to Boston in exchange for Wade Miley and Jonathan Aro. The 26-year-old put up impressive numbers in his first full season last year, working to a 2.31 ERA with a strong 92:22 K:BB ratio in 70 innings and figures to see high leverage opportunities in the back end of the Boston bullpen.

Smith has now served as the setup man rather than take the ball in the ninth inning in the Mariners' last two save situations.

EDGE Analysis

He recorded his second straight four-out hold while serving as the bridge to Tom Wilhelmsen in the ninth inning Tuesday. Smith would seem to be a better pitcher than Wilhelmsen by almost any statistic, but nonetheless, it seems that a change has taken place in the pecking order for saves in Seattle's bullpen.

Smith will continue to get save opportunities despite Fernando Rodney being called upon in the ninth inning Friday, as the role will continue to be situational, the Seattle Times reports. Manager Lloyd McClendon said he used Smith in the eighth inning Friday against the Angels' Albert Pujols and Mike Trout because he wanted to use his best reliever in the most important spot of the game. Kudos to McClendon for not managing by the save rule. Smith, Rodney, Charlie Furbush and Mark Lowe could see save chances based on matchups and situations. Eventually, though, McClendon said he'd like to see Rodney return to ninth-inning duty. "That's my hope," Mclendon said. "But I don't know if that's going to happen or when it's going to happen. For right now, we'll keep doing what we're doing."

Smith got two outs in the eighth inning Friday in Anaheim, while Fernando Rodney came on in the ninth and recorded the save. This could simply be a managerial decision by Lloyd McClendon to get Smith in the game against Mike Trout and Albert Pujols (who both reached base against him before an inning-ending double play), or it could signal a return to closing for Rodney. Smith's certainly done nothing to lose the job, recording five saves without blowing any since he was moved into the role in early June, but his owners would do well to monitor this situation closely.

Smith struck out one during a perfect ninth inning Friday against the Astros to earn his fourth save of the season. The 25-year-old lowered his ERA to 1.59 on the season and earned his fourth save in four attempts. Smith appears to be in firm control of the closer's role for Seattle and should be the top option in save situations for the foreseeable future.

Smith got the ninth-inning call Friday instead of embattled closer Fernando Rodney, earning his first career save with a perfect inning. Manager Lloyd McClendon said after the game that Rodney, who has allowed runs in nine of his last 13 appearances, would get some time off to work on his mechanics. Smith likely will see more save chances, but McClendon said other relievers will get ninth-inning work too. Smith is the closer-in-waiting to own, though, as he has a sinking fastball that gets groundouts, a sidearm slider for right-handers and a plus changeup he likes to use on lefties.

Mariners manager Lloyd McClendon is sticking with Fernando Rodney as the closer and doesn't yet believe that Smith is an alternative. This despite Rodney's blown save Tuesday and general poor results this season. "I don't have that guy right now," McClendon said of alternatives. "I know people point to Carson Smith, but he's a young kid. We have to be careful with him, particularly with his innings and back-to-back-to-back [appearances]. I'm not sure he can do that. I think his velocity goes down quite a bit. He's one of those young men that still doesn't have his man muscles, so to speak. He needs to mature and continue to develop."

With Danny Farquhar having been demoted to Triple-A on Monday, Smith is now the unchallenged second chair behind embattled closer Fernando Rodney. Rodney nailed down his 13th save with a scoreless inning Monday night, but he's been patently awful this year, with a 5.89 ERA and 1.58 WHIP. Meanwhile, Smith -- who collected his ninth hold with a perfect eighth inning Monday -- has been one of the best relievers in baseball so far this year, so Farquhar probably wasn't a major threat to him anyway. However, it's worth noting that he's seen a lot of work in the early going, as Monday marked his 22nd appearance in 44 games -- an 81-game pace.

Smith picked up his eighth hold of the season Saturday, throwing a perfect eighth inning and striking out one. He's been nothing short of excellent so far, and Smith now boasts a 0.90 ERA and 23:5 K:BB ratio in 20 innings. Fernando Rodney has been very shaky lately despite having only one official blown save, and if the Mariners do decide to make a switch at closer, Smith is the obvious candidate to replace him.

Smith struck out Mike Trout with two on to end an eighth-inning threat in Monday's season-opening win against the Angels. Smith struck out Trout on four pitches, and the lone non-strike was on a check-swing. Smith, following an out by lefty Charlie Furbush, was cleaning up a mess created by Danny Farquhar. Of course, it's just one game (and Farquhar started slowly last year too), but it's worth keeping an eye on how Farquhar and the power-arm Smith are used. Farquhar is the closer-in-waiting to Fernando Rodney, but it's not out of the question that he could be jumped by Smith if his struggles last.