ARLINGTON, Texas. -- Seattle Mariners Executive Vice President & General Manager of Baseball Operations Jerry Dipoto announced today that the club has acquired minor leaguers Aaron Fletcher (lhp), Taylor Guilbeau (lhp) and Elvis Alvarado (rhp) from the Washington Nationals in exchange for Roenis Elías (lhp) and Hunter Strickland (rhp).

Guilbeau, 26, is ranked as the No. 15 prospect in the Nationals organization by MLB.com. He has split time in the minors this season between Double-A Harrisburg and Triple-A Fresno in the Nationals organization. With Harrisburg, he went 1-2 with a 2.31 ERA (9 ER, 35.0 IP) with 10 walks and 44 strikeouts over 27 games before being promoted to Fresno on July 11. In 7 games with Fresno, he is 2-0 with a 5.19 ERA (5 ER, 8.2 IP) with 5 walks and 6 strikeouts. In total, he has gone 3-2 with a 2.89 ERA (14 ER, 43.2 IP) with 15 walks and 50 strikeouts over 34 games in the minors this season.

Guilbeau originally signed with the Nationals after being drafted in the 10th round of the 2015 MLB First-Year Player Draft out of the University of Alabama. He has spent 5 minor league seasons in the Nationals organization, posting a 16-12 record with a 4.05 ERA (154 ER, 342.0 IP) with 93 walks and 300 strikeouts in 126 career games (39 starts).

Fletcher, 23, is ranked as the No. 21 prospect in the Nationals organization by MLB.com. He is 5-4 with 1 save and a 1.79 ERA (12 ER, 60.1 IP) in 32 relief appearances combined between A Hagerstown, High-A Potomac and AA Harrisburg this season. The 6-foot-0, 220-pound, left-handed reliever has limited opponents to a .167 (36x216) average, while walking 15 and striking out 69 over 60.1 innings. Since June 6, he is 3-1 with a 0.90 ERA (3 ER, 30.0 IP) in 16 games combined between Potomac (11 G, 6/6-7/11) and Harrisburg (6 G, 7/15-30). Fletcher opened the season appearing in 15 games with Hagerstown in the South Atlantic League, going 2-3 with 1 save and a 1.61 ERA (5 ER, 28.0 IP). He was promoted to Potomac on May 29. After allowing 4 runs in 2.1 innings in his first outing on June 1 at Myrtle Beach, Fletcher did not allow an earned run over his final 23.2 innings (6/6-7/15). During this 11-game stretch he limited opponents to a .114 (9x79) average while walking 7 and striking out 27. He made his AA debut with Harrisburg on July 18, appearing in 5 games in relief.

In 2 minor league seasons, Fletcher is 7-5 with 1 save and a 2.17 ERA (22 ER, 91.1 IP) in 45 games, 7 starts. He has limited opponents to a .208 (70x337) average, while walking 19 and striking out 103. Fletcher was originally selected by Washington in the 14th round of the 2018 MLB Draft out of the University of Houston. During his junior year at the University of Houston in 2018, he was named American Athletic Conference Pitcher of the Year, leading the league with a 2.19 ERA.

Alvarado, 20, began his professional career as an outfielder but converted to pitcher in 2018. In 7 games (2 starts) with the Gulf Coast League Nationals, the 6-foot-4, 175-pound right-hander is 2-2 with a 6.00 ERA (10 ER, 15.0 IP) with 19 strikeouts and 16 walks. In 10 outings with the GCL Nationals in 2018, he posted a 6.59 ERA (10 ER, 13.2 IP) while striking out 13 and walking 12. He was originally signed by Washington as a non-drafted free agent on July 10, 2015. The native of San Ignacio de Sabaneta, Dominican Republic, appeared in 55 games as an outfielder with the DSL Nationals (45 G) and the GCL Nationals (10 G) over the 2017 and 2018 seasons.

Strickland, 30, has made 4 relief appearances for the Mariners this season while missing most of the year with a right lat strain. In 4 outings with the Mariners, he is 0-1 with 2 saves (in 3 opportunities) while striking out 3 and allowing 3 runs in 3.1 innings pitched (8.10 ERA). He began the season by earning the save in each of the Mariners first 2 games (March 20 and 21 vs. Oakland in Tokyo). On March 29 vs. Boston, he was removed from the game after giving up a pinch-hit home run to Mitch Moreland and allowing 3 runs in 0.1 innings pitched. He was originally placed on the 10-day IL on March 30 and transferred to the 60-day IL on April 1. After making 3 relief appearances on a rehab assignment with Triple-A Tacoma, he was reinstated from the 60-day Injured List on July 28.

Strickland was signed by Seattle as a free agent on Jan. 27, 2019. In parts of 6 Major League seasons with San Francisco (2014-2018) and Seattle (2019), he is 14-15 with 21 saves and a 2.98 ERA (76 ER, 229.1 IP) with 214 strikeouts and 79 walks in 257 career games. He made his Major League debut with the Giants on Sept. 1, 2014 at Colorado. He was originally selected by Boston in the 18th round of the 2007 MLB Draft out of Pike County High School in Zebulon, GA.

Elías, 30 (turns 31 on Aug. 1), went 4-2 with 14 saves (in 16 opportunities), 1 hold and a 4.40 ERA (23 ER, 47.0 IP) in 45 relief appearances for the Mariners this season. The 5-foot-11, 205-pound left-hander struck out 45 and walked 17 while allowing 8 home runs. From June 7 – July 2, he was 6-for-6 in save opportunities while posting a 0.90 ERA (1 ER, 10.0 IP) in 9 outings. In 5 outings from July 3-20, he allowed 8 earned runs in 3.2 innings pitched (19.64 ERA). Since July 22, he is 2-0 and 3-for-3 in save opportunities while tossing 4.1 scoreless innings. 

Elías was acquired by the Mariners from Boston in exchange for a player to be named later or cash considerations on April 23, 2018. It marked his second stint with the club after originally signing with the Mariners as a minor league free agent out of Cuba on May 3, 2011. He made his Major League debut on April 3, 2014 at Oakland. On December 7, 2015, Elías was acquired by Boston, along with Carson Smith (rhp), in exchange for Wade Miley (lhp) and Jonathan Aro (rhp). In parts of 6 Major League seasons with the Mariners (2014-15, 2018-19) and Red Sox (2016-17), he has a career record of 22-24 with 14 saves and a 4.02 ERA (172 ER, 385.0 IP) while striking out 323 and walking 147 in 122 career appearances (54 starts).