AMERICAN Jennifer Capriati gave her tennis rehabilitation further authenticity with a fighting three-sets victory over compatriot Chanda Rubin at the Sydney International tournament yesterday.

Capriati, out to wipe the slate clean after drug and shoplifting charges which all but snuffed out her precocious tennis career three years ago, rebuffed the higher-ranked Rubin, 6-3, 4-6, 6-3 in a 103-minute opening-round match.

Capriati, 21 in March and ranked 36th in the world, was imbued by her success over the highly-regarded Rubin and gave promise of making a go of her tennis career after her seamy past.

Beaming her trademark smile, Capriati announced "I'm back" after mastering the 17th-ranked Rubin and the notorious unsettling winds on White City's centre court.

"It's a great boost, it's like I'm back and that I still have what it takes to beat a player like Chanda and it shows I've come a long way since I played her last time," Capriati said of her last meeting with Rubin in Indian Wells, California, last March.

Assessing her strengths since she broke into the tennis world as a 14-year-old in 1990, Capriati said: "I think overall everything is stronger, I don't know if that is because I am older, more mature . . . it's not like little kids' tennis any more."

Capriati, fatigued by tennis `burn-out' and following regular spats with her father-coach Stefano, dropped out of the Tour near the end of 1993.

In December, 1993, she was arrested on a shoplifting charge in Florida and in May, 1994 she was charged with possession of marijuana and had two stints in drug rehabilitation clinics as penance.

Yesterday, Capriati was typically strong on her forehand, hitting 10 winners to Rubin's eight, and she was equally powerful on the backhand, outscoring her opponent, 8-3.

Her next round opponent will be Canadian Rene Simpson and her chances of repeating her 1993 Sydney tournament triumph were further improved when top seed Arantxa Sanchez Vicario, in her top half of the singles draw, was upset by American Amy Frazier, 6-3, 6-3. It was the Spaniard's first opening-round defeat as a top seed in a tournament.

Sanchez Vicario was not the only top seed to crash out yesterday. South African second seed Wayne Ferreira fell to Spaniard Carlos Moya, 2-6, 6-0, 6-3, while former French Open champion Sergi Bruguera eliminated fellow Spaniard and fifth seed Felix Mantilla, 7-6 (7/5), 6-3.