Halle Opne: Roger Federer battles hard to secure semifinal spot

World number one Roger Federer was tested once again in Halle but did enough to overpower Australian Matthew Ebden 7-6(2) 7-5 in the quarter-finals on Friday.

Nine-time Halle champion Federer, who saved two match points to beat Benoit Paire in the second round, edged a tense opening set against 60th ranked Ebden in the tiebreak with a backhand winner.

Ebden was leading 5-3 in the second set against the 36-year-old before the Swiss fought back to secure four consecutive games to set-up a semi-final against American Denis Kudla.

Federer extended his grasscourt streak to 19, which includes the Stuttgart title and last year's triumphs at Wimbledon and Halle. Qualifer Kudla, ranked 109th in the world, eased past Japan's Yuichi Sugita 6-2 7-5 earlier in the day.

Kudla progressed to only his second semi-final at ATP tour-level when he roared back from a 2-5 deficit in the second set and saved a set point in the process.