Updated at 7:50 p.m.
The Nationals have sent Michael Morse back to Seattle and are getting A.J. Cole back from Oakland in the process.
Morse was part of a three-team trade involving the Nationals, Athletics and Mariners, with Cole (one of the prospects sent to Oakland in last winter's Gio Gonzalez blockbuster) among the three players acquired by Washington, the club officially announced this evening.
The Nationals received two more players from the A's in addition Cole: minor-league right-hander Blake Treinen and another player to be named. Oakland, meanwhile, receives catcher John Jaso from Seattle.
Thus ends Morse's productive and popular, 3 1/2-year stint with the Nationals. Originally acquired from the Mariners for outfielder Ryan Langerhans in 2009, the slugger burst onto the scene two years later when he took over for an injured Adam LaRoche at first base and led the club with 31 homers, 95 RBI and a .303 batting average.
It was LaRoche's strong return from that 2011 shoulder injury, though, that helped make Morse expendable in the end. After winning both the Gold Glove and Silver Slugger awards last season, the veteran first baseman was re-signed for two years and a guaranteed $24 million.
At the same time, the Nationals traded for center fielder Denard Span from the Twins, bumping Bryce Harper to a corner outfield position and leaving no remaining lineup spots for Morse.
Though they could have kept the 30-year-old as a talented-but-pricey ($6.75 million) bench bat, the Nationals preferred to attempt to trade him and acquire prospects in the process. By sending Morse to a Mariners team that desperately needs the offensive help, general manager Mike Rizzo also gives Morse a chance to put up big numbers before he becomes a free agent next winter.
Morse's departure will be noticeable in the Nationals' lineup, in their clubhouse and in the stands, where he became a fan favorite both for his prodigious power and quirky "walk-up" songs.
Rizzo made it clear he was looking for quality pitching prospects in a trade, and he managed to re-acquire a familiar face in Cole. The 21-year-old right-hander was selected by the Nationals in the fourth round of the 2010 draft and immediately became one of the best young arms in a well-stocked farm system.
The depth of that system convinced Rizzo to include Cole in the blockbuster deal that landed Gonzalez one year ago, a trade that also sent prospects Tommy Milone, Brad Peacock and Derek Norris to Oakland.
Cole opened last season at high-Class A Stockton and struggled mightily, going 0-7 with a 7.82 ERA in eight starts. He was subsequently demoted to low-Class A Burlington, where he rediscovered his form, posting a 2.07 ERA in 19 starts to close out the year.
Treinen, 24, was Oakland's seventh-round pick in the 2011 draft out of little-known South Dakota State. A 6-foot-4 right-hander, he went 7-7 with a 4.37 ERA in 24 games (15 starts) last season for high-Class A Stockton. He dealt with some arm trouble last season but possesses a 95 mph fastball. Some believe he'll profile eventually as a late-inning reliever.