MELBOURNE, Jan 15: Roger Federer and Amelie Mauresmo led a parade of champions into the second round of the Australian Open on Monday while police ejected about 150 tennis fans from the grounds after Croatian and Serbian fans clashed.

Fighting flared for the first time at a grand slam event after spectators exchanged insults during the match between Croatian Mario Ancic and Japan's Go Soeda. Police said no arrests were made.

The clashes failed to overshadow the on court action on the opening day of the Open, with Croatian fourth seed Ivan Ljubicic becoming the most notable casualty.

Ljubicic's 4-6, 7-6, 6-4, 6-4 battering by Mardy Fish was his second successive opening-round flop in grand slams.

Mauresmo was the first to take centre stage in her defence of the women's crown, brandishing winners from all angles to consign American Shenay Perry to a 6-3, 6-4 defeat.

Men's champion Federer overcame a wobbly first set before gliding to a 7-5, 6-0, 6-4 victory over Bjorn Phau as he began his pursuit of a 10th Grand Slam title.

They were joined in the last 64 by former winners Serena Williams and Thomas Johansson, with 2005 champion Marat Safin offering the late-night action.

A tortured and tormented Andy Roddick provided the early drama.

The American staggered into round two after dousing the fireworks produced by a little-known Frenchman.

Jo-Wilfried Tsonga had barely registered on the tennis radar until his trip to Melbourne Park.

So low is his ranking, that he does not even merit an entry in the ATP handbook. But he penned his name into tennis folklore when he won a marathon first-set tiebreak 20-18, equalling the record for longest breaker in the tournament's history.

The 212th-ranked wildcard, however, was unable to sustain his heroics and despite being a set and 5-2 up he went down fighting 6-7, 7-6, 6-3, 6-3, much to the relief of the sixth-seeded American.

The fired-up American was left fuming and swearing at 10-10 in the first set tiebreak when he thought the 21-year-old Tsonga's shot had landed beyond the baseline.

After Roddick was reduced to even swatting the ball on bended knees, 10-10 went on to 15-15 and then 18-18 – thus eclipsing the famous 18-16 tussle between Bjorn Borg and John McEnroe in the 1980 Wimbledon final.

Just when as it seemed there was no end in sight, a netted error from Roddick handed Tsonga the set if not the match.

The American, though, cannot afford such lapses again as he is heading for a third-round collision with Safin.

Germany's Phau held the rare distinction of holding a winning record over Federer – thanks to coming out on top in their solitary meeting in 1999 – but that accolade lasted just one hour and 47 minutes in the stifling heat on Rod Laver Arena.

After producing some erratic shots in the first set, when he was broken three times, Federer was back to his sublime best.

The only blip Mauresmo had was when she was a set and 5-1 up. Perhaps blinded by Perry's fluorescent lime green outfit, Mauresmo went on to lose three games on the trot but regained her focus in the nick of time to close out a 74-minute win.

Serena Williams, on a comeback trail after a four-month injury layoff, lit up the night session with an even louder version of Perry's ensemble. She shook off the rust from her game to win 6-2, 6-1.

Third seed Svetlana Kuznetsova led a sextet of Russian women into the second round. She was joined by fifth seed Nadia Petrova, seventh seed Elena Dementieva, Maria Kirilenko, Elena Vesnina.

Olga Poutchkova earned the unenviable task of taking on Mauresmo following a 6-2, 6-4 win over Poland's Marta Domachowska.

Results: