Infielder Hector Guevara has been promoted from high-Class A Charlotte to the Biscuits.
The 21-year-old was hitting .245 with six home runs and 32 RBIs in 60 games for the Stone Crabs. Montgomery was short an infielder after shortstop Shawn O'Malley went on the disabled list Thursday with an abdominal strain.
Guevara, who had a .234 average in 100 games at Charlotte last year, has primarily been a second baseman in his career. He's played shortstop 50 times in his 4 1/2-year career, including seven games this year.
Guevara's best pro season so far was his first. In 2009, he was the Venezuelan Summer League Rays' most valuable player after hitting .330 with eight home runs and 36 RBIs in 54 games.