The Mariners continued their offseason search for offensive upgrades by acquiring Nationals outfielder/first baseman Mike Morse on Wednesday in a three-way deal that sent catcher John Jaso to the A's.
Oakland traded three prospects to the Nats to complete the deal.
Morse, 30, gives Seattle another middle-of-the-order bat as he returns to the Mariners after 3 1/2 seasons with the Nationals.
Morse hit .298 and averaged 24.5 home runs and 78.5 RBIs the last two years despite missing the first 60 games last season with a back injury. He's in the final year of a contract that pays him $6.75 million in 2013.
Jaso, 29, figured to be the Mariners' backup catcher behind Jesus Montero this coming season after hitting .276 with 10 home runs and 50 RBIs in 108 games in 2012.
Seattle obviously will be in the market to add another backstop, with Montero now the only catcher on the 40-man roster. The club does have 2012 first-round Draft pick Mike Zunino waiting in the wings, but figures to also pursue a veteran as well.
Jaso was one of four Mariners who filed for salary arbitration on Tuesday. He is in his first season of arbitration eligibility and will be under the A's team control for three years after earning $495,000 in 2012.
The Mariners have now added first baseman/designated Kendrys Morales, infielder Robert Andino and outfielders Raul Ibanez, Jason Bay and Morse this offseason.
General manager Jack Zduriencik had been pushing to acquire D-backs outfielder Justin Upton until that deal fell through when Upton blocked a trade to Seattle last week.
Morse joins a Mariners outfield competition that now includes Michael Saunders, Franklin Gutierrez, Casper Wells, Eric Thames, Carlos Peguero, Ibanez and Bay.