Atlanta manager Brian Snitker confirmed that Muller will be called up from Triple-A Gwinnett to start one game of Monday's doubleheader with the Mets, Mark Bowman of MLB.com reports.
Ian Anderson will start the other doubleheader game, but Atlanta has yet to decide whether Anderson or Muller will get the ball for the first contest. Muller made his MLB debut last week against Boston in a relief role, giving up two runs on four hits over an inning of relief. He's fared better over his seven starts with Gwinnett, compiling a 4.90 ERA, 1.51 WHIP and a 41:19 K:BB in 31.1 innings.