Crowds have been mixed at the tournament but Zheng has been a consistent draw in Saudi Arabia, with a large number of Chinese fans cheering her on against Krejcikova.
Her game is simple: a big serve, followed up by an equally thumping groundstroke, which initially worked to great effect against Krejcikova.
She moved well around the court, bullying Krejcikova out of rallies before the Czech took advantage of a dip in her form to force the second set back to 3-3.
Zheng grew increasingly frustrated – not helped by her service game twice being held up by a crying baby – and her shots grew wilder, but she kept herself in touching distance of Krejcikova.
A thunderous backhand return of serve gave Zheng break point at 5-5, and she duly took it on a long Krejcikova forehand to serve for the match.
Although Krejcikova again pushed her, with Zheng having to fend off another break point, she ultimately claimed a straight-set win as the Czech went wide with a forehand.
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