No manlets at the top level in tennis. Height is the biggest advantage possible in tennis. It's more important than strength, explosiveness, speed, reflexes, and cardio.
If you look at the US open, you have multiple guys the height of Stefan Struve competing at this US Open: John Isner, Kevin Anderson, etc. Then you just tons and tons of 6'6" guys: Cilic, Del Potro, just tons of guys. "Short" in tennis today is like 6'-6'1".
The 6'10-7' guys in tennis can barely walk, have terrible groundstrokes, just terrible -- even worse than Struve's skillset in the UFC. They're awful. But height is just such an advantage that they still kick ass.