Both Burriss and Velez, whose Triple-A Fresno season ended Monday evening, will be in uniform and available to play in San Francisco's evening game in Arizona on Tuesday. The position-player pair will be joined by their Minor League manager, Steve Decker, who will help out as an ancillary coach.
Burriss, who played in three games for the Giants between Aug. 9 and 13, batted .280 and stole 11 bases in 66 games at Fresno this season. He gives San Francisco another option on defense and on the basepaths in late innings.
Velez batted .302 in 82 games for Fresno but struggled in his previous stints with the Giants, batting .196 in limited playing time. In a pinch, he can play second base and the outfield.
Other candidates to be called up that were not include utility man Ryan Rohlinger and right-handed pitchers Kevin Pucetas, Waldis Joaquin and Henry Sosa.
Major League clubs were allowed to expand their rosters from 25 to 40 players on Sept. 1. San Francisco now has 32 active players.