Isaac won't play Thursday in the Rays' Spring Breakout game against Red Sox prospects due to a sore left wrist/elbow, Marc Topkin of the Tampa Bay Times reports.
Outfielder Matthew Etzel was added to the roster as a replacement for Isaac, who was reassigned to minor-league camp Sunday. Isaac first experienced soreness in his left arm in late February, resulting in him being limited to designated hitter duties in his final four Grapefruit League games prior to being reassigned. The Rays had intended to get Isaac some reps in the corner outfield in addition to first base this spring, but the elbow injury has thwarted those plans. Isaac should be ready to go for the start of the minor-league season in late March, but it's uncertain whether he'll be cleared to play first base by then.