Janowicz, the No. 7 seed, defeated Lukas Rosol 6-2, 6-4 in 63 minutes in the first main-draw match of the tournament. He dropped just 13 points over nine games serving and didn't face a break point.
Bernard Tomic followed with a 4-6, 3-6, 7-6 (9-7) upset of the eighth-seeded Klizan. Tomic saw just two break points -- although he lost both -- in 16 service games. He won 72 percent of the points on serve but Klizan was nearly as effective, winning two-thirds when he served.
Neither player established much of an advantage in the third set until Tomic edged ahead at the end.
The Open 13 tournament features five Top 10 players, including world No. 6 Tomas Berdych, who is the top seed. Juan Martin del Potro, seventh in the world and seeded second, is the defending champion.