The Nationals are 54-36 this season, the third-best record in baseball and second-best behind the Dodgers in the National League despite 14 blown saves this season.
Madson, 36-year-old, joined the Athletics four years after Doolittle, but debuted with the Philadelphia Phillies in 2003.
"Losing those two guys will be tough, and I know the guys will feel it a little bit too, but we're in a little different course right now, and we really like the guys that we're bringing back", Melvin said. He's only tossed 74 innings since 2015, but has a 3.41 ERA and 91 strikeouts during that period. He has been putting together yet another outstanding season, pitching to a 3.38 ERA in 23 games. He finished 3-for-5 in save chances with a 5.73 ERA with Washington this season.
Treinen started the season as the Nats closer but fell out of favor quickly.
Luzardo, 19, was a third-round draft pick in 2016 and is 1-0 with a 1.32 ERA at the Gulf Coast Rookie League Nationals in his return from Tommy John surgery on March 22 past year.
Left-hander Jesus Luzardo and infielder Sheldon Neuse were sent to Oakland as part of Sunday's deal. Luzardo fell in the 2016 draft because he underwent Tommy John surgery on March 22, 2016 during his high school career at Stoneman Douglas High (Fla.).
He also has been dominating left-handed batters this season. Neuse has broken out this season with the Low-A Hagerstown Suns, hitting.291 with 9 home runs and 51 runs batted in over 77 games.
To the surprise of many, Madson is the better pitcher this year. "There are no hard feelings". And the players involved made it particularly painful for many A's fans.
Ken Rosenthal of Fox Sports reported the news.
Rizzo said he wasn't sure when Madson and Doolittle would be joining the Nationals.
The A's opted for Santiago Casilla as their closer this season, but Madson has pitched well, compiling a 2.09 ERA with 39 strikeouts in 39.1 innings. After showing he could be an effective late-inning reliever again, Madson signed a three-year deal with the A's and racked up 30 saves for them last season. Although Madson's contract isn't as team-friendly as Doolittle's, it is still reasonable for a pitcher with his experience and talent. Doolittle is owed the rest of his $2.6 million this year, $4.35 next season with a $6 million club option for 2019 and a $6.5 club option for 2020.