Updated

Towering American John Isner snuck into the third round, while seventh-seeded Argentine Juan Monaco was ousted at the $3.5 million Shanghai Masters, the eighth of nine ATP Masters events this year.

The 6-foot-9 eighth-seeded Isner battled South African Kevin Anderson over three sets on Day 3, as the North Carolina native saved three match points before prevailing after three tiebreaks, 7-6 (7-3), 6-7 (8-10), 7-6 (9-7), as neither player was able to break serve in a big-hitting affair on the hardcourts at Qizhong Tennis Center.

Isner needed 2 hours, 46 minutes to advance, as the American swatted 24 aces, while Anderson chimed in with 21 in a losing effort.

"Really we both served well," said Isner. "It's one of the few times where, I don't think I was out served, but he served right up there with me as far as aces, percentages, what not. So we both were serving exceptionally well. It came down to a few points here or there, and I was able to pull it out. It was looking bleak for a little bit. I served well enough to maybe win in two sets, but I had to win in three. I'm very, very excited to get through. I know I easily could have lost that one."

Also in the second round, Spanish left-hander Fernando Verdasco doused Monaco 6-4, 6-2 and 10th-seeded Croat Marin Cilic handled Slovak Martin Klizan 7-5, 6-1. Monaco titled in Malaysia two weeks ago.

Four seeds saw opening-round action on Tuesday.

Twelfth-seeded Canadian Milos Raonic topped Aussie qualifier Marinko Matosevic 7-6 (7-4), 6-3; 13th-seeded Swiss Stanislas Wawrinka bested Spaniard Albert Ramos 7-6 (7-1), 7-6 (7-5); hot 14th-seeded Japanese Kei Nishikori dismissed Chinese wild card Di Wu 6-2, 6-4; and 15th-seeded Frenchman Gilles Simon pasted struggling Austrian southpaw Jurgen Melzer 6-4, 6-2. The surging Nishikori is fresh off his title in Tokyo where he upset Raonic in the final last week.

In another first-round bout, Czech veteran Radek Stepanek drove out wild card and former world No. 1 Aussie Lleyton Hewitt, 7-5, 6-1.

Additional opening-round wins came for Cypriot Marcos Baghdatis, Serb Viktor Troicki, Spaniard Feliciano Lopez, German Florian Mayer, Taiwan's Yen-Hsun Lu, and Uzbekistan's Denis Istomin.

The second round will conclude on Wednesday with 13 matches, including ones for top seeds Roger Federer, Novak Djokovic and reigning two-time Shanghai champ Andy Murray. The 2010 Shanghai runner-up Federer will face the qualifier Lu, while last week's Beijing titlist Djokovic will encounter Bulgarian Grigor Dimitrov and the U.S. Open champion and Olympic gold medalist Murray will meet Mayer.

The British star Murray captured his second straight Shanghai title by beating Spaniard David Ferrer in last year's finale.

The 2012 Shanghai champ will collect $669,450.