Montero, the Mets' sixth-ranked prospect, posted a 4.87 ERA in two starts and one relief appearance, actually reducing his season ERA to 5.23. He had produced a 5.40 mark over his first four career starts in May, originally receiving a big league callup before deGrom.
The latter has leapfrogged Montero on the depth chart, leaving him to work out his kinks in the Minors. Montero has had few issues there this season, going 6-3 with a 3.28 ERA in 15 starts for Las Vegas. The Mets could call him back up as a reliever once rosters expand in September, hoping to keep his innings total around 185-190.
Anthony DiComo is a reporter for MLB.com. Follow him on Twitter @AnthonyDicomo. This story was not subject to the approval of Major League Baseball or its clubs.