Third seed Tsvetana Pironkova was the biggest casualty on the opening day of the Budapest Grand Prix as the Bulgarian fell 1-6 6-3 6-1 to Georgia's world number 81 Anna Tatishvili.
Seventh seed Shahar Peer was also beaten 6-4 6-3 to Aleksandra Wozniak of Canada, while fourth seed Klara Zakopalova had to fight to avoid a similar fate before beating Briton Anne Keothavong 7-6 (7/3) 3-6 6-2.
Fifth seed Marina Erakovic squeezed past Pauline Parmentier of France 7-6 (7/3) 3-6 7-6 (7/2) while sixth seed Petra Martic was too good for Hungary's Csilla Borsanyi, winning 6-0 7-5.
Hungarian favourite Greta Arn was surprised 3-6 6-3 6-1 by Lesia Tsurenko of Ukraine, but the hosts did enjoy some success with wild card Vanda Lukacs beating Henrietta Habler 6-2 6-1. Russia's Elena Vesnina also advanced.