scoreless innings in relief, earning the win. Throughout the season, Elías was typically used as a long reliever or spot starter, finishing 2018 with a 2.65 ERA, 154 ERA+, 3.08 FIP, and 2.13 strikeout-to-walk ratio in 23 appearances (51.0 IP), including 4 starts. Following the departure of All-Star closer Edwin Díaz in the 2018 offseason as well as an early-season injury to newly-acquired closer Hunter Strickland, Elías was used exclusively out of the bullpen especially in high leverage situations, ultimately becoming the team's new closer. In 44 games (47.0 IP) with the Mariners in 2019, he pitched to a 3.64 ERA with 14 saves. 45 strikeouts, and 17 walks. Washington Nationals On July 31, 2019, the Mariners traded Elías and Hunter Strickland to the Washington Nationals in exchange for Aaron Fletcher, Taylor Guilbeau, and Elvis Alvarado. Elías made his Nationals debut on August 2, 2019, recording the final two outs of the sixth inning. However, he was forced to leave the game and was placed on the 10-day injured list after he pulled his right hamstring running down the first-base line during an at-bat the following inning. In 2019 he pitched three innings for the Nationals. Between the Mariners and the Nationals combined in 2019, he was 4-2 with 14 saves and a 3.96 ERA, as in 48 relief appearances he pitched 50.0 innings. The Nationals finished the 2019 year with a 93-69 record, clinching the wild card, and eventually won the World Series over the Astros. Elias was not part of the Nationals' postseason run, but still won his first world championship. Elias was outrighted off of the Nationals 40-man roster on October 9, 2020, and elected free agency the next day. Third stint with Mariners On January 7, 2021, Elías signed a minor league contract with the Seattle Mariners organization. On March 16, it was announced that Elias had suffered a torn ulnar collateral ligament that required Tommy John surgery and cause him to miss the 2021 season. On March 26, Elías was released by the Mariners. On April 1, Elias re-signed with the Mariners on a new minor league contract. On May 16, 2022, Elias was selected to the active roster. He made one relief appearance for the Mariners, allowing one earned run on one hit and two walks against the Toronto Blue Jays. On May 19, Elias was removed from the 40-man roster and returned to