August 11, 2017
The Situation: Mark Reynolds is nursing a sore hand, so the Rockies might be able to use an infielder with some defensive flexibility and a .354/.401/.587 line in the upper minors this year.
The Background: McMahon was drafted 42nd overall in 2013 out of Mater Dei High School in California. A prep shortstop, he was moved to third base as a pro and mashed his way to Double-A in short order, posting .500+ slugging percentages at each of his stops on the minor league ladder. He hit a speed bump in Hartford last year, struggling with the jump to Double-A to the tune of .242/.325/.399. A return engagement to the Insurance City went much better—and the cozy confines of the new stadium didn't hurt either—and he’s continued to mash in Albuquerque.
Scouting Report: McMahon’s calling card is power to all fields. He generates plus bat speed and serious leverage from his lean, athletic frame. He can handle premium velocity with aplomb, and the power plays in games even to left-center. During his 2016 struggles, McMahon tended to drop his back shoulder and sell out for pull side power, trying to lift and yank everything. He’s been much more under control this year, but there are still swing-and-miss issues against spin and southpaws. You have to squint to see an average hit tool here, but McMahon has enough approach and feel to get a chunk of that plus raw into games
With Nolan Arenado entrenched at third base for two more years, McMahon started to play some first base last season in his first go-round in Hartford. This year, he added second base to his repertoire as well. Third is probably his ideal defensive home long term. He’s still a solid fielder at the hot corner, with soft hands and an above-average arm. He’s still a little raw at first, especially with his footwork around the bag. I didn’t see him at second base this year, but got reports that amounted to “he won’t kill you there” and hey, he was a high school shortstop.
Immediate Big League Future: Much like with Tapia, there isn’t a clear path to an everyday role for McMahon with the 2017 Rockies. But his positional versatility and lefty power bat fits a little better on a major league bench than Tapia’s hit-tool driven corner outfield profile. McMahon may see more regular time at first if Mark Reynolds hand issue lingers or worsens, but he is unlikely to unseat the possibly-blind baseball masher. —Jeffrey Paternostro
Fantasy Impact: With Nolan Arenado firmly entrenched at third base for the Rockies, many thought McMahon might have "No Chance in Hell" for a call up to Coors Field. Shows what "many" know. McMahon will join the squad this weekend, primarily set to man the cold corner (fine, so I guess that prognostication was sort of correct). A, let's say, streaky (read: bad) 2016 led McMahon to be widely cast aside in prospect circles, but the 22-year-old has more than made up for it, absolutely mashing across two levels this season. His reemergence has culminated with a .375/.409/.625 line in 269 plate appearances at Triple-A Albuquerque, which according to my calculations is, um, good. He didn't walk a ton (which is fine if you're hitting almost .400), but he didn't strike out much either, cutting down on his whiffs significantly this season after struggling in years past.
Jeffrey Paternostro is an author of Baseball Prospectus. Follow @jeffpaternostro