World No. 15 Monfils beat Australia's Marinko Matosevic 7-6 (7-5) 6-3 6-3 to earn a tie with Brazil's Thomaz Belluci, who eliminated Israel's DudiSela.
The Croatian defeated fourth-seeded Serbian Janko Tipsarevic 6-1 6-3 on Saturday, while Wawrinka beat Israeli fifth seed DudiSela 6-4 2-6 7-5 in the other semifinal.