On January 17, 2008, Aybar was traded along with Chase Fontaine to the Tampa Bay Rays for Jeff Ridgway. On March 24, 2008, it was announced that he would be the starting third baseman for the 2008 Tampa Bay Rays. He held this position until Evan Longoria was called up early in the season. Aybar then took the role of utility player. He finished the season batting .253 with 10 home runs and 35 RBI in 95 games. In the field, Aybar started 40 games at third base, 18 at first base, 14 at designated hitter, six at second base, and two at shortstop.