Chennai, Jan 7 :  Top seed Tomas Berdych, despite struggling with his serve, had enough firepower to knock out unfancied Blaz Kavcic 6-3, 6-3, to enter the semi-finals of the Aircel ATP Chennai Open tennis tournament here Friday.

On the outside court, Xavier Malisse, the seventh seeded Belgian, extended his hold on Bjorn Phau from Germany with a 6-0, 6-2 win in 71 minutes that witnessed long baseline rallies. He too moved into the penultimate round.

Berdych, World No. 6 and 2010 Wimbledon finalist, was rather patchy against Slovenian Kavcic who has never beaten a player ranked higher than himself (112).

The match witnessed as many as seven service breaks, six of them in the second as both struggled to get into any kind of rhythm or flow during the one-hour and 24-minute contest.

Kavcic, winner of three Challenger titles last year and playing his first ATP tour quarter-final, showed plenty of determination to stay with his better-equipped rival, but ultimately, the Czech proved far too formidable once he got his act together.

For the 2007 champion Mallise, it was his third win over the German in as many meetings and he has dropped just 12 games in seven sets to Phau who in the first round had knocked out fourth seeded Frenchman Richard Gasquet.

Phau's achievement was par for the course as he has never got past the quarter-finals in six appearances in this tournament while Malisse remains the only former winner remaining in the singles draw.

The results: Singles (quarter-finals): 7-Xavier Malisse (BEL) bt Bjorn Phau (GER) 6-0, 6-2; 1-Tomas Berdych (CZE) bt Blaz Kavcic (SLO) 6-3,6-3.(IANS)