Where Does Luke Scott Fit In?

Luke Scott began his rehab assignment with the Charlotte Stone Crabs on Friday. After struggling in his first game back, when he went 0-4 with three strikeouts, Scott is now hitting .286 with a home run, three runs scored, and two RBIs in his four games of action for the Stone Crabs.
Scott is presently considered to be close to returning to action, as his rehab has progressed without problem. However, when he returns, what role will he have? An outfielder by trade, he has yet to play in the field this season due to surgery on a shoulder injury sustained last season. His spot at designated hitter has been taken over by Evan Longoria, who is not yet ready to play in the field after his return from a partially torn hamstring.
With those options taken, it would appear as though Scott would be a part time player, being used as a pinch hitter or at DH when Longoria needs a day off. However, there may be another option. Scott has played a total of 42 games at first base over his career, with 32 of them coming since 2010. Playing first base would allow the Rays to get his bat into the lineup, while minimizing the strain on his shoulder. The Rays would also have an option other than putting Carlos Pena in the lineup each day. Yet, Scott is below league average defensively as a first baseman, with a .988 fielding percentage and a range factor of 7.55, far below the .994 fielding percentage and the 9.19 range factor for an average first baseman. Pena, for his struggles offensively, is still an above average defender at first base.
As the Rays have struggled both offensively and defensively for most of the year, this likely comes down to which problem Joe Maddon feels is most pressing. Scott could potentially start at first base, get a few at bats, then be replaced by Pena in the late innings for defensive purposes.
Is there a place for Luke Scott in the lineup? The Rays may have to make that decision very soon.