Red Sox acquire right-handed pitcher Carson Smith and left-handed pitcher Roenis Elias from Seattle

Send left-handed pitcher Wade Miley and right-handed pitcher Jonathan Aro to the Mariners

The Boston Red Sox today acquired right-handed pitcher Carson Smith and left-handed pitcher Roenis Elias (roh-EN-ees ehl-LEE-us) from the Seattle Mariners in exchange for left-handed pitcher Wade Miley and right-handed pitcher Jonathan Aro.
 
President of Baseball Operations David Dombrowski made the announcement.
 
Smith, 26, went 2-5 with 13 saves, 22 holds, and a 2.31 ERA (18 ER/70.0 IP) in 70 relief appearances for the Mariners as a rookie last season. With 92 strikeouts in 2015, he ranked fourth among American League relievers and posted the AL's seventh-highest strikeout rate out of the bullpen (11.8 SO/9.0 IP). Among AL relievers since 1990, only Dellin Betances (135 in 2014), Joel Zumaya (97 in 2006), Francisco Rodriguez (95 in 2003), and Troy Percival (94 in 1995) have recorded more strikeouts in a single rookie season. Smith had the third-highest ground ball rate (65.4) among AL bullpen arms and ranked among that group in innings (5th), opponent OPS (5th, .539), holds (T-8th), opponent batting average (9th, .194), ERA (11th), and WHIP (13th, 1.01).  
 
Smith, who made his big league debut as a September call-up in 2014, is 3-5 with a 2.07 ERA (18 ER/78.1 IP) and 102 strikeouts compared to just 25 walks allowed in parts of two major league seasons. From 2014-15, he set Mariners records with 20 scoreless appearances and 19.1 scoreless innings to begin his career. A native of Dallas, TX, he was signed by Seattle as an eighth-round selection in the 2011 June Draft.
 
Elias, 27, has spent parts of the last two seasons with Seattle, going 15-20 with a 3.97 ERA (123 ER) and 240 strikeouts in 279.0 innings over 51 career big league outings, all but two as a starter. In two stints with Seattle last season, he was 5-8 with a 4.14 ERA (53 ER/115.1 IP) and 97 strikeouts in 22 appearances, including his first two relief outings in the majors. Elias, who posted a 2.79 ERA (18 ER/58.0 IP) in his first nine starts of 2015, gave up one earned run or less in six starts, two or less in 11 starts, and three or less in 15 of his 20 starts in 2015.
 
A 10-game winner in 2014, Elias went 16 consecutive starts allowing no more than three earned runs from July 2014 through late May 2015, tied for the second-longest such streak among American League left-handed pitchers over the past two seasons. He threw a complete game three-hit shutout in his 12th career major league appearance on June 1, 2014 against Detroit, and also has a pair of 10-strikeout games in the majors, on May 1, 2014 at the New York Yankees and on June 19, 2015 against the Houston Astros. A native of Cuba, Elias was signed by the Mariners in May 2011. He also pitched for Guantanamo in Cuba's major league, Serie Nacional, before defecting in late 2010.
 
Miley, 29, made his Red Sox debut in 2015, leading the club in wins (11-11), starts (32), innings pitched (193.2), and quality starts (17). Acquired by Boston from Arizona in December 2014, the left-hander finished the season with a 4.46 ERA (96 ER) and 147 strikeouts, falling just shy of his third consecutive 200.0-inning campaign. The Louisiana native has made at least 32 starts in each of his last three seasons, with his 98 starts in that time ranking first among left-handed pitchers and tied for third in the majors. Named an All-Star in his first full season with Arizona in 2012, Miley is 49-46 with a 3.95 ERA (365 ER/832.1 IP) in 138 career appearances (134 starts) between the Diamondbacks and Red Sox.
 
Aro, 25, made his major league debut with the Red Sox in 2015, going 0-1 with a 6.97 ERA (8 ER/10.1 IP) in six games after having never pitched above Single-A prior to the season. A native of La Vega, Dominican Republic, the right-hander received the organization's 2015 Lou Gorman Award for overcoming adversity to reach the major league club. He spent the majority of the season between Double-A Portland and Triple-A Pawtucket, combining to go 3-3 with two saves and a 3.04 ERA (25 ER/74.0 IP) and .212 opponent batting average (58-for-274) in 34 appearances, all in relief. Signed by the Red Sox as an international free agent on June 6, 2011, Aro has gone 16-15 with 13 saves and a 2.83 ERA (95 ER/301.2 IP) in 101 career minor league appearances (12 starts).