Russian second seed Nikolay Davydenko fell to Germany's Florian Mayer 6-4 6-4 in the second round of the Halle Open on Thursday.

On a bad day for Russians at the grasscourt tournament, sixth seed Mikhail Youzhny was forced to pull out with a back injury 24 hours before his scheduled quarter-final against Tomas Berdych.

Berdych, the fourth seed from the Czech Republic, goes straight through to the semi-finals.

Jarkko Nieminen of Finland and eighth seed Marcos Baghdatis of Cyprus joined Mayer in the quarter-finals by winning close matches on Stadium Court.

Nieminen overcame Andrei Pavel of Romania 7-6 3-6 6-1, while Baghdatis, a semi-finalist at Wimbledon last year, recovered to beat Sweden's Robin Soderling 6-7 6-4 6-3.

After losing the first set, Baghdatis, seeded eighth, quickly went a break down in the second and it needed a great comeback to see him through to the last eight.

"I tried to play like a goalkeeper -- just choosing one corner to go for -- and it worked out," he said.

Davydenko's defeat by Mayer was no real surprise given how much the Russian has struggled on grass over the years.

The 26-year-old has never won back-to-back matches on the surface and he never looked likely to here as Mayer kept him pinned back.

(Writing by Kevin Fylan in Berlin)