Alexander Zverev to face Stan Wawrinka in St Petersburg Open final

German teenager Zverev got the better of Czech veteran Tomas Berdych 6-4 6-4 in his semi-final, before this month's US Open winner Wawrinka also came through in straight sets - but only after a tough match against Roberto Bautista Agut.

Nineteen-year-old Zverev, seeded five, overturned the odds against Berdych in under an hour-and-a-half.

He had to hold his nerve to close out victory, saving three break points in the final game to serve out the match after two deuces.

Wawrinka then needed more than an hour-and-a-quarter to edge a titanic opening set 10-8 in the tie-break, but he had an early break in the second and went on to beat Spaniard Agut 7-6 6-2.

In the Moselle Open, Lucas Pouille's victory over former champion David Goffin salvaged some French pride after number one seed Dominic Thiem had inflicted a home defeat on Gilles Simon.

Thiem faced a semi-final opponent with an impressive Metz pedigree following Simon's tournament win in 2013 and runner-up spot last year.

This time Simon went a set up but could not close out the second and ran out of steam as the Austrian prevailed 4-6 7-5 6-3.

Goffin then pushed Pouille all the way in the first-set tie-break, but conceded two early breaks in the second and eventually lost it 6-1 as his 22-year-old opponent moved one step away from a maiden tour title.