Both Whalen and Povse have potential as big-league starting pitchers, and Whalen has already tasted life in MLB (5 starts with Atlanta in 2016). Look for Whalen to challenge for the No. 5 starter role in Seattle, while Povse should move to Triple-A Tacoma at some point. This is a solid deal for the Mariners.

Atlanta obviously sees much untapped potential in Jackson, who was selected sixth overall in the 2014 draft. Jackson has struggled as an outfielder during his time in the Mariners' system but may move back to catcher with the Braves. Jackson was drafted as a catcher, so the familiarity might help him.

Whalen and Povse have long-range fantasy upside and should now be on the radar in most leagues. Jackson is another story. As a catcher, he has some dark-horse appeal for keeper leagues. However, if he stays in the outfield, he will have to produce far more just to make it onto the fantasy radar.