With Monday's opening day action rained out, Tuesday saw eight first-round matches on the hard courts at the Dusit Resort.
Tanasugarn roared past eighth-seeded Anastassia Rodionova, 6-2, 6-, to the delight of her countrymen. Another first-round upset saw No. 6-seeded Yaroslava Shvedova dropping a 3-6, 7-6 (7-4), 6-3 decision to Bychkova.
Fifth-seeded Angelique Kerber and No. 7-seeded Jill Craybas, who were to have played Monday, escaped the upset bug Tuesday. Kerber was solid in a 6-3, 7-5 win over Meng Yung and Craybas routed Olga Savchuk, 6-1, 6-1.
Other winners Tuesday were Olga Poutchkova, Akgul Amanmuradova, Lilia Osterloh and Renata Voracova.
The tournament continues through the week with the winner of Sunday's finals collecting $25,650.
Ray Liotta sues skin care company over use of likeness
Boston schools pull out free condoms over wrapping complaints