Updated at 5:15 p.m.
Trying to bolster a talented bullpen that has appeared worn down in recent weeks, the Nationals acquired veteran left-hander Matt Thornton off waivers from the Yankees.
The Nationals aren't giving up a player in a trade for Thornton; they simply were awarded a waiver claim and thus are responsible only for picking up his contract. The 37-year-old reliever is owed roughly $1 million for the rest of this season, then another $3.5 million in 2015.
Thornton provides the Nationals a veteran left-hander with a longstanding track record. He owns a 2.55 ERA in 46 appearances this season, striking out 20 while walking only six in 24 2/3 innings. Used primarily as a match-up specialist in New York, he has held left-handed hitters to a .556 OPS this season.
Over an 11-year career spent mostly with the White Sox, though,Thornton has enjoyed success against both lefties and righties, producing a 3.49 ERA while holding right-handed hitters to a .241 batting average and left-handed hitters to a .234 batting average.
"He's having one of his best years," manager Matt Williams said. "His splits are good, lefty-righty. Fastball velocity is really good. And he's been there and he's done that. Pitched in the playoffs and has that experience under his belt. He just adds veteran leadership and veteran presence to the bullpen. But he can do both roles. He can face righties as well."
Thornton was en route from New York to Washington late Tuesday afternoon, Williams said, so it was unclear if he would make it in time for the series opener against the Mets. For now, he's not listed on the Nationals' active roster for the game, with the rest of the bullpen intact. One of those relievers, most likely Blake Treinen, will need to be removed once Thornton arrives.
"Certainly when stuff like this happens, there's a lot to do in a short period of time," Williams said. "So we don't know exactly when he'll be here. He'll be activated when he does get here. We just don't know when that will be."
To clear space on their 40-man roster for Thornton, the Nationals transferred Class AAA right-hander Taylor Jordan from the 15-day DL to the 60-day DL.
Thornton bolsters a bullpen that has looked worn down in recent weeks. One of the majors' most-effective relief corps through the season's first half, that group has given up 18 runs over its last 20 2/3 innings. Several key pitchers — notably Rafael Soriano, Tyler Clippard and Drew Storen — all have needed multiple days off in the last week due to excessive use.
"I think the biggest pressing issue with that is lack of days off," said Williams, whose team is in the middle of a stretch of 17 consecutive game days. "Games dictate how you pitch guys and what you do, certainly the back of your bullpen. But the lack of days off will push that even further. So, does [Thornton] help in that regard? Yeah. His innings count is down this year, as compared to his appearances. So he's fresh. So it'll do nothing but help."