Question: Which tennis player Anna-Lena Grönefeld or Mats Wilander turned professional first ?
Sentence (from "Mats Wilander"): From 1982 to 1988, he won seven Grand Slam singles titles (three at the French Open, three at the Australian Open, and one at the US Open), and one Grand Slam men's doubles title (at Wimbledon).
Relevant evidence: Yes