Gonzalez Gathering Pace; Roddick Cuts Down Karlovic

© Getty ImagesFernando Gonzalez meets former Top 10 Tomas Berdych in the first round for the second straight year.

Fernando Gonzalez maintained his perfect record in tour-level quarter-finals this season as he edged out the in-form Tommy Haas 7-5, 6-4 Friday to book his spot in the semi-finals of the Legg Mason Tennis Classic, an ATP World Tour 500 tennis tournament in Washington, D.C.

The fourth seed, who is now undefeated in five tour-level quarter-finals this year, was made to work hard for his 27th victory of the season against a resilient Haas, who was bidding to reach his fourth tour-level semi-final in a row.

Dominant serving from both Gonzalez and Haas in the first set – they surrendered just two and three points respectively behind their first serves – led to a lack of break point chances. But Gonzalez was quick to pounce with the one chance he created in the 11th game, breaking to lead 6-5 before closing out the one-set lead after 45 minutes.

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Gonzalez looked to be on his way to a more comfortable second-set score line as he broke twice to race out to a 5-2 lead. The No. 23-ranked Haas gave the Chilean food for thought as he recouped one of the breaks, but Gonzalez held strong to close out victory at the second time of asking, after 83 minutes.

The 29-year-old Gonzalez is one win away from reaching his second final in Washington, D.C., having defeated then World No. 1 Andre Agassi in the 2003 semi-finals before falling to Great Britain’s Tim Henman in the title match. He captured his 11th ATP World Tour title earlier in the season as he successfully defended his trophy in Vina del Mar (d. Acasuso).

Haas, 31, suffered his third quarter-final exit in Washington, D.C. as he dropped to a 26-12 mark on the season. The former World No. 2 has been rejuvenated of late, clinching his 12th ATP World Tour title in Halle (d. Djokovic) and reaching the Wimbledon semi-finals (l. to Federer) before opening his Olympus US Open Series campaign with a semi-final showing in LA (l. to Querrey) last week.

In the semi-finals Gonzalez will face defending champion Juan Martin del Potro, who advanced with a walkover over Robin Soderling when the Swede was forced to withdraw with a right elbow injury. The Roland Garros finalist will have an MRI today to determine the extent of the injury and whether he will play in the Rogers Masters, an ATP World Tour Masters 1000 event in Montreal, beginning Monday.

Looking ahead to his clash with del Potro, Gonzalez said, “We are really good friends. We have a few years in age difference, but we are really good friends.”

Gonzalez revealed that he took an extended break from the practice court immediately after Wimbledon to rest his right knee, which is affected by tendinitis.

Del Potro said of his walkover from Soderling: “It is very unfortunate Robin  couldn’t play today. I was looking forward to this match against Robin as he has been playing incredibly well in the past months. I am sure it would have been a close match.”

Gonzalez takes a 3-0 career lead into the clash with the second-seeded Argentine, although the pair has not met since the 2007 Australian Open. The 20-year-old del Potro has since risen to No. 6 in the South African Airways 2009 ATP Rankings after a major breakthrough last summer, when he went on a 23-match winning streak that included four successive ATP World Tour titles and finished in a quarter-final loss to Andy Murray at the US Open.

“I played a very long match against Hewitt yesterday so this day off will help me to recover better for my semi-final match tomorrow against Gonzalez. I’ve lost to him three times in my career and I hope I can get my first win tomorrow,” said del Potro.