Karlovic Saves 2 M.P. To Beat Isner; Fish's Top 10 Dream Shattered

© Aaron M. Sprecher/ROCCIvo Karlovic hit 24 aces and won 70 per cent of service points to beat John Isner.

Qualifier and 2007 titlist Ivo Karlovic saved two match points in the tense third set tie-break to beat fourth seed John Isner 7-6(2), 6-7(2), 7-6(9) Friday for a place in the US Men's Clay Court Championship semi-finals. And in the featured night match, Japan's Kei Nishikori ended top seed Mardy Fish's quest to break into the Top 10 for the first time in his career with a commanding 6-3, 6-2 win.

In the battle between the two tallest players on the ATP World Tour, there were just two breaks of serve in the match - in back-to-back games at 5-all and 5-6 in the second set - but Karlovic was forced to fight off 10 other break point chances on his serve. Isner, who fired 23 aces, faced only one break point in the match.

Karlovic hit 24 aces en route to victory in three hours and 16 minutes. The 6' 10" Croatian has now hit 44 aces for the tournament, which is 16 aces shy of the all-time tournament record set by Pete Sampras in 2002. Karlovic also hit 50 aces in three qualifying matches earlier in the week.

It was just the fourth match at the ATP World Tour 250 clay-court tournament (since 1988) to have all three sets decided in a tie-break. The others include, 1995 - Magnus Larsson defeating Jared Palmer; 2000 - Martin Rodriguez beating Lorenzo Manta; and last year when Xavier Malisse edged Isner.

Karlovic led 5-2 in the third set tie-break and squandered two match points at 6-4. Isner saw two of his own match points go the way of Karlovic at 7-6 and 9-8. It was the pair's third ATP World Tour tournament meeting.

World No. 174 Karlovic advanced to his first semi-final since February 2010 at Delray Beach, where he reached the final. Isner, who hit 23 aces and won 76 per cent of service points, drops to an 8-8 season record.

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American wild card Ryan Sweeting reached his first ATP World Tour semi-final after he defeated Teymuraz Gabashvili of Russia 3-6, 6-3, 6-1 in one hour and 41 minutes.

World No. 93 Sweeting, who dropped one point on serve in the deciding set, converted five of seven break point opportunities overall to improve to an 8-6 match record on the season.

Uruguay’s Pablo Cuevas advanced to his first semi-final since Moscow last October when he won his first meeting with doubles partner, Spaniard Guillermo Garcia-Lopez, 1-6, 7-6(4), 6-3. Former World No. 14 Cuevas has slipped to No. 75 in the South African Airways 2011 ATP Rankings. He next plays Japanese sixth seed Kei Nishikori, a surprise 6-3, 6-2 winner over top-seeded American Mardy Fish.

Fish, who won his lone ATP World Tour clay court title in Houston in 2006, hit just one ace and did not earn a break point on Nishikori's serve. At No. 11 in the South African Airways 2011 ATP Rankings, Fish would have broken into the Top 10 for the first time in his career had he won a second Houston title. Nishikori was appearing in his first ATP World Tour quarter-final on clay.

"He didn't give me too much and seemed pretty comfortable with his backhand," Fish said. "I struggle at night; sometimes I feel I can't necessarily do some of the things I want to do because I don't have that split second to pick the ball up earlier than I normally do. I love to stay more agressive; standing 15-20 feet behind the baseline trying to stay in the points is not my game. [But tonight] that was strategic as I thought that was the best way to have a good clean hit on the ball... he seemd to enjoy that.

On missing the chance to break into the Top 10, Fish said, "It's disappointing, especially at a place like Houston where I have great memories. It would have been a nice place to do it, especially in the States. And being the No. 1 American is a responsibility each time you step on the court."

Nishikori said: "I don't think [Mardy] played great today," Nishikori said. "He missed a lot. I played good enough to beat him and played good clay court tennis. I was trying to run him around and hit hard to his forehand. I returned well today."