Tipsarevic knocked off Paul-Henri Mathieu of France 7-6 (12-10), 6-3 Saturday, and Belluci battled past Grigor Dimitriov of Bulgaria 7-6 (7-3), 7-6 (7-5).
Tipsarevic is the World No. 8 men's player and Mathieu is ranked 173rd. "The first set could have gone either way," Tipsarevic said after the match. "I think he went for too much in some occasions in the second set and I was just more solid than him."
Bellucci and Dimitriov swapped service breaks twice in the battle of unseeded contestants. Bellucci came away with a 2-0 edge in the decisive tie-breaks.
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