Kuerten wants more rigourous testing on the Tour

All of the players, including Britain's Greg Rusedski, were cleared but Kuerten says players are now worried about what they are putting into their systems.

"It's very scary at this stage in the locker room," says the world number 10.

"Normal guys like me don't want to get involved with drugs. I don't see anyone using drugs to take advantage."

Low levels of the banned performance-enhancing drug nandrolone were detected in the eight players' samples last year.

We have a timetable to recommend solutions ATP president Chris Clouser

They were cleared of any wrongdoing because the ATP had been handing out nutritioinal supplements - some of which were contaminated.

ATP chiefs, players representatives, coaches and medical experts met ahead of this week's Miami Masters Series event to discuss concerns over the tainted supplements.

"Our meeting was an initial step in the right direction," said ATP president Chris Clouser.

"We have a tight timetable over the next few months to both compile information and recommend solutions."

Two more task force meetings are scheduled in the next five months, the next one will take place in Hamburg in early May.