Ivo Karlovic banged down 21 aces as he upset 13th seed Gael Monfils 6-4, 6-7, 7-6 in the first round of the Cincinnati Masters Monday. The 6-feet-10 (2.08 meters) Croat, who beat Roger Federer on his way to the semifinals last year, won the deciding tiebreak 7-2 to advance to the second round after two hours, 10 minutes. After taking the first set thanks to one break, Karlovic led 5-4 in the second-set tiebreak, with two serves to come, but Monfils reeled off three superb points in a row to force a decider. The Frenchman saved three break points in the fourth game of the third set but Karlovic played a superior tiebreak to move through to a clash with another Frenchman, Paul-Henri Mathieu, a 6-7, 7-5, 6-3 winner over German Mischa Zverev. Ninth seed Gilles Simon eased into the second round with a 6-3, 6-2 win over American wildcard Wayne Odesnik. He will now play Russian Igor Andreev, who beat Nicolas Kiefer of Germany 6-1, 7-5. Croatia's 14th seed Marin Cilic beat former world number one Juan Carlos Ferrero 6-3, 6-4. He will play David Ferrer of Spain in the second round after he beat Stanislas Wawrinka of Switzerland 7-5, 6-2. Jose Acasuso of Argentina set up a second-round meeting with world number one Federer by beating Lukasz Kubot of Poland 6-4, 6-3. Ivan Ljubicic, Benjamin Becker and Nicolas Almagro also advanced in the day's early action. World number six Juan Martin del Potro withdrew from the tournament, citing fatigue, organizers said. The Argentine was beaten by Andy Murray in the final of the Montreal Masters Sunday, having also won a tournament in Washington the previous week. Del Potro is replaced in the draw by lucky loser Julien Benneteau of France. The temperature had already topped 80 degrees as Rafael Nadal pushed himself through his morning workout Monday, swatting balls around the court for a sweaty hour and 45 minutes. He wished for more. The 23-year-old Spaniard feels his limitations every day during his comeback from two months off the tour to let his aching knees rest and heal. Normally, he would have practiced another 45 minutes to get ready for his opening match this week at the $3 million Cincinnati Masters. Now, he can't do it. “I need to go slow, no?” he said, after the workout. Going slow means not pushing too hard at his second tournament back on the tour. It means accepting that he won't be anywhere near his best when the US Open starts in two weeks.
