Diaz has been dealing with hamstring tightness that hasn’t resolved quite as rapidly as had been hoped. The club obviously felt it could no longer afford to carry an unavailable players.
There’s little reason at present to think that Diaz will be sidelined for more than the minimum, though it’ll all depend upon how the muscle heals up. The Rays will hope for a swift return for the 27-year-old, who has been everything they hoped for and more since arriving via trade.
Diaz has racked up 248 plate appearances of .286/.363/.502 hitting and 11 home runs on the season. That’s just the sort of output the Tampa Bay organization got last year from Robertson, but he scuffled to open the current campaign and ended up on optional assignment. There’s now a bit of a window for him to reclaim a MLB role, though there isn’t as much opportunity with Joey Wendle back in action.