Nadal, bidding for a record-equalling 20th Grand Slam trophy, claimed victory when Carreno Busta sent a backhand into the net, set up a meeting with Australian Nick Kyrgios for a spot in the quarter-finals.
Kyrgios, no stranger to controversy, sparked headlines when he mocked Nadal by imitating the Spaniard's pre-service routine after being hit with a time violation during his second-round match on Thursday.
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Nadal, who had earlier brushed aside the incident, said he preferred Kyrgios more when he was playing his fiery brand of tennis instead of drawing attention for his on-court antics.
"When he plays good tennis and he shows passion for this game, he is a positive player for our tour and I want my tour bigger, not smaller," he said.
"When he's ready to play his best tennis and play with passion, (he) is one of these guys. When he's doing the other stuff, of course I don't like."
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