HOUSTON, TX, USA - Peng Shuai secured her spot in the semifinals by beating Whitney Osguigwe in straight sets at the Oracle Challenger Series Houston WTA 125K event.

Peng - who vanquished top seed Belinda Bencic in the last round - took the first set 6-2, but the young American battled to assume control of the second set with a break of serve to move ahead 5-3.

The veteran fought back, though, to break right back and eventually force a tiebreak, emerging victorious 6-2, 7-6(3), for her first straight-sets win of the week so far.

She will face Jessie Pagula, who beat Fanny Stollar 6-3, 6-3.

Elsewhere, 18-year-old Sofya Zhuk brushed past Britain's Heather Watson 7-5, 6-4 to secure her semifinal spot against Lauren Davis.

The qualifier beat Katherine Sebov 6-1, 6-3 to continue her impressive run.