Cruz is 1-1 with a 2.61 ERA and 32 strikeouts against 17 walks in 31 innings this season. He landed on the DL in mid-July with shoulder inflamation.
Hughes, meanwhile, was 2-1 with a 2.70 ERA and 32 strikeouts against 18 walks in 56.2 innings pitched. He has been one of the Pirates' most productive relief pitchers this seasons, but those numbers hide recent struggles. In his last four appearances spanning six innings pitched, Hughes has given up six earned runs and two home runs. He gave up three earned runs in one inning against the Diamondbacks on Aug. 7, which led to a 10-4 loss.
This move will give Hughes a chance to work on getting his stuff back into top form. He will likely be one of the top candidates to return to the club when rosters expand of Sept. 1 if not sooner.