The Seattle Mariners picked up a left-handed pitcher for their MLB bullpen on Wednesday. That's Caleb Ferguson. But the Mariners had to trade away an intriguing prospect to get the deal done, giving the Pittsburgh Pirates back a young arm with a great name.

The Pittsburgh Pirates have traded left-handed reliever Caleb Ferguson to the Seattle Mariners. The deal was first reported by MLB.com’s Mark Feinsand and others before being announced by the Pirates on Wednesday night. Pittsburgh acquired right-handed pitching prospect Jeter Martinez in a one-for-one deadline deal.