Czech Republic's comprehensive 3-0 victory against the USA in Gelsenkirchen on Monday came at a price as striker Jan Koller suffered a serious thigh injury.

The giant frontman was stretchered off shortly before half-time in the World Cup Group E clash and coach Karel Bruckner fears his tournament could be over.

"Unfortunately his injury is very serious," said Bruckner. "It is the only negative thing from today's match."

Tomas Rosicky, who scored two superb goals to secure the man of the match award, admitted Koller's injury had tempered his enjoyment of the game.

"We may have lost Koller and that makes this game tough to take," said Arsenal's new signing.

"But we're really satisfied with the win and how we played. We had problems early on, we couldn't get our timing right.

"It improved halfway through the first half and I think we controlled the ball much better after that.

"They were tough opponents. I am not sure the score indicates how tough they were."