Davis Cup teammates Lleyton Hewitt and Marinko Matosevic led an Aussie assault as the unseeded pair gate-crashed into the second round of the ATP Tour\'s Atlanta Championships. Former number one Hewitt on Tuesday connected on a superlative 89 percent of his first-serve points (25 of 28) in a 6-4, 6-4 crushing of American qualifier Phillip Simmonds. Matosevic, ranked 69th and a first-round Wimbledon victim, upset Russian sixth seed Igor Kunitsyn 6-7 (3/7), 6-2, 7-5. Taiwan\'s Lu Yen-Hsun, a winner over German Matthias Bachinger 7-5, 7-6 (7/4) will be the next opponent for Matosevic, who earned his first ATP victory of the season from six starts. It was only the second victory of his career on the Tour. Hewitt, the 30-year-old former number one and two-time grand slam winner now dependent on wild cards after his ranking sunk to 174th, is coming back strong from his spring foot surgery, which came in the wake of a pair of hip operations in recent years. He is playing at his lowest ranking since March 9, 1998, during his first full year on the ATP. He now stands 9-7 on the season. \"The ball was bouncing very high due to the heat,\" said, the winner. \"It was tough to control and it took awhile to get used to things. \"I served smarter as the match went on, that made things a bit easier for me.\" Hewitt, with 28 career titles, is playing a full hardcourt schedule this season prior to the US open, and hoping for free entries into Masters 1000 tests in Montreal and Cincinnati next month based upon past performance. If he cannot make a substantial rise over the next month, the 2001 winner could possibly find himself playing qualifying if a New York wild card does not materialise. Hewitt next takes on Rajeev Ram of the US, who upset Bulgarian fifth seed Gregor Dimitrov 6-4, 6-4. In other results to complete the opening round, 19-year-old Ryan Harrison, - youngest player in the field - put out Japan\'s Yuichi Sugita 6-1, 7-6 (7/5) while Robby Ginepri won his first match since last August following a mountain bike crash caused by a runaway squirrel, defeating former number two Tommy Haas 6-4, 7-5. The German is making a comeback from hip surgery and was seeking a second win of the season after returning to the courts at the French Open. Holder Mardy Fish will begin on Wednesday against Nicolas Mahut after the Frenchman beat Richard Berankis of Lithuania 7-6 (7/5), 6-2.