Ivo Karlovic put the brakes on Mikael Ymer's Stockholm Open fairytale with a come-from-behind victory in Wednesday's second-round match.
World number 549 Ymer had stunned Fernando Verdasco - ranked 505 places above him - in the first round for his maiden ATP Tour win.
But powerful veteran Karlovic proved an obstacle too far, the 37-year-old earning a 4-6 6-4 6-4 triumph.
Juan Martin Del Potro beat John Isner 6-4 7-6 (8-6) in a first-round contest, while Germany's Alexander Zverev beat Adrian Mannarino 7-5 6-4 to reach the quarter-finals.
Jack Sock and Jurgen Zopp were first-round victors in Wednesday's other matches.