Question: Which olympic tennis player, Rennae Stubbs or Juan Martín del Potro, competed in the most Olympic games? 
Sentence (from "Juan Martín del Potro"): Other career highlights include winning the bronze medal in men's singles at the 2012 London Olympics and the silver medal at the 2016 Rio Olympics and being part of his country's successful Davis Cup team; but his career has also been hampered by a succession of wrist injuries.
Relevant evidence: Yes