Shaffer is the key to the deal for Seattle, as he brings a ton of home-run power to the table. He can play both first and third base and is also insurance at the DH spot. He will head to spring training with a chance to earn significant playing time at first base. He may wind up in a platoon, though. As for Motter, he has definite appeal in Major League Baseball due to his ability to play all over the infield and outfield. He should compete for a utility man role in spring training.

The Rays did not really have a position for Shaffer to play, with Evan Longoria entrenched at third base and former Mariner Brad Miller emerging last season as the first baseman. Therefore, they moved both Shaffer and Motter to the Mariners for three prospects. Thompson is the best of the bunch, though he is only 20 years old. Kittredge is a versatile right-hander who might be able to help th Rays as early as 2017. As for Kelly, he is an intriguing first base prospect.

Shaffer's fantasy value has been given a boost after this trade, provided he is able to win a starting job out of spring training in March. Otherwise, he will most likely be used in a backup role. Motter does not have much fantasy value because his best asset is his versatility. Thompson is now squarely on the keeper-league radar but will not be rushed to the bigs. Kittredge and Kelly are wait-and-see prospects at this point.