Gael Monfils soars to superhero heights on court.
So what happens when Sliderman goes up against a couple of Spidermen in a game of vertical tennis in Rotterdam?
Watch: Top 5 One-Handed Backhands
Watch Monfils hit to a couple of guys hanging off a building wall.
It was all a promotion for this week's ABN AMRO World Tennis Tournament.
Tournament director Richard Krajicek stole the show.
At about 58 seconds into the video, the former Wimbledon champion, once one of the biggest servers on the ATP Tour, hits a titanic shot to connects with the wall hanger.
Photo credit: Mark Peterson/Corleve