Opportunity knocked for Gamel in 2017, and he responded with a surprisingly productive season. A 10th-round pick in 2010, he hit .318 from the time of his callup in late April until the end of July (83 games). Gamel faded in a major way down the stretch with a .198/.236/.335 line over the final two months, and those numbers are probably more indicative of who he is as a player rather than the ones he posted before the break. The 25-year-old turned in middling strikeout (22.2 percent) and walk (6.5 percent) rates, resulting in just a .315 wOBA, and the "expected" numbers from Statcast were ugly (.290 xwOBA, .244 xBA). Gamel was a net negative in the field, and given the fluky nature of his offensive numbers, another season of 500-plus plate appearances is no lock. He may be lucky to get to 400 even, as the Mariners could upgrade in left field at some point and relegate Gamel to a bench role.

Gamel won the International League Rookie of the Year award in 2015 and followed it up with the International League Most Valuable Player award in 2016. In late August, the Yankees wound up trading the potential Brett Gardner clone to the Mariners, who gave him a handful of starts down the stretch. The 24-year-old could eventually club 10 homers and steal 20 bases annually if his skills reach their peak, and the trade helps his avenues for playing time in the immediate future. Seattle will probably allow him to compete for a starting gig during spring training, and Gamel's defensive versatility will help his chances. Those in AL-only leagues should consider stashing him in one of their reserve spots.