Two Russians and a German have been ejected from the Porximus Diamond Games after ushers spotted them betting online in the stands during matches, officials have confirmed.

The opening-day incident Monday at the WTA tournament was among the first reported since a new crackdown on possible corruption and match-fixing in the sport.

A tournament spokesman credited sharp-eyed ushers, who noticed the trio with the laptops open to online gambling pages. They were believed to be exploiting the split second between the time a point was played and actually registered on the official online scoring page to place online bets.

"The ushers saw them in the stands with computers open," said an official. "They told us and we spoke with the WTA. They had the chance to give up their computers or to leave - they left."

The three had their pictures taken to prevent any further attempts at entry later in the week of an event which ends on Sunday and features world No. 1 Justine Henin as top seed.