The 28-year-old Sjodin, seeking her first LPGA title, battled a tricky wind to finish tied with the world No. 1 at 9-under 207 after 54 holes at the Dinah Shore Tournament Course.
Sjodin missed the cut at last week's Kia Classic, while Tseng is vying for her third straight victory in five starts overall this season. The latter, however, struggled to 1-under 71 Saturday.
The pair finished the day two strokes ahead of Haeji Kang (72).
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