MELBOURNE (AFP) - Match-fixing is commonplace in tennis' lower levels and efforts to fight it are inadequate, a senior anti-corruption official told AFP after cheating claims rocked the sport during the Australian Open.

After an explosive report claimed match-fixing was repeatedly going unpunished, Chris Eaton of the International Centre for Sport Security (ICSS) criticised tennis' "opaque and secretive" anti-corruption body.

The controversy is just the latest to hit the tainted sports world after claims of a doping cover-up shook athletics and multiple scandals engulfed football's governing body, Fifa.

Eaton, directory of integrity at the ICSS, said professional betting analysis showed "nil manipulation" of matches at the top levels of tennis, where players are highly paid and less susceptible to bribery.

"However in the second and lower levels, manipulation indicators are heavy and regularly occurring," the former Fifa security chief said via e-mail.

"We are not the only sport integrity organisation to observe this."