Tatishvili ousted Pironkova 1-6, 6-3, 6-1. Pironkova took two-thirds of the points in the first set but Tatishvili turned things around and won nearly 60 percent of the points the rest of the way.
Aleksandra Wozniak also advanced with an upset, knocking out seventh-seeded Shahar Peer 6-4, 6-3. Wozniak had six breaks over Peer's nine games serving.
Two other seeded players needed third sets to get out of the first round, Fourth-seeded Klara Zakopalova got by Anne Keothavong 7-6 (7-3), 3-6, 6-2 and No. 5-seeded Marina Erakovic edged Pauline Parmentier 7-6 (7-3), 3-6, 7-6 (7-2).
Also Monday, sixth-seeded Petra Martic beat Csilla Borsanyi 6-0, 7-5; Vanda Lukacs stopped Henrietta Habler 6-2, 6-1 in a battle of local wild-card entrants; Lesia Tsurenko eliminated Greta Arn 3-6, 6-3, 6-1; and Elena Vesnina was up 5-0 when Varvara Lepchenko retired.