Thompson (back) began a throwing program Monday, Alex Weiner of ArizonaSports.com reports.
Arizona placed Thompson on the 15-day injured list Aug. 5, so his ability to start throwing soon after being deactivated suggests that he won't be in line for an extended stay on the shelf. Thompson had collected seven holds and four wins while pitching to a 4.43 ERA and 1.57 WHIP in 40.2 innings over 46 appearances out of the Arizona bullpen prior to landing on the IL.