KUALA LUMPUR, Sept 25 — Fifth seed Alexander Zverev of Germany stunned top seeded US Open winner Stanislas Wawrinka today for his maiden ATP title at the home of his parents at the St Petersburg Open.

Zverev, 19, was stretched to go the distance to win a tight match 6-2, 3-6, 7-5 against Swiss Wawrinka, Reuters reported.

Wawrinka won the US Open in New York on September 11.