McGuire will be promoted from Triple-A Salt Lake to the big leagues Wednesday, Jeff Fletcher of The Orange County Register reports.
McGuire was optioned to the minors Tuesday, but he's set to return to Los Angeles nearly 24 hours later. He's made eight appearances (two starts) in the big leagues this season, accruing a 6.41 ERA and 1.47 WHIP with an 18:10 K:BB over 19.2 innings.