Question: At 2006 Dubai Tennis Championships – Men's Singles, Rafael Nadal defeated the defending champion who has won how many Grand Slam singles titles?
Sentence (from "2017 Australian Open – Men's singles final"): In a rematch of the 2009 Australian Open final, which Nadal won in 5 sets, Roger Federer won the duel in 5 sets, beating Nadal for the first time in a Grand Slam since the 2007 Wimbledon final.
Relevant evidence: No