Monfils out of Davis Cup semi-final

Gael Monfils has been forced to withdraw from France's Davis Cup semi-final against Croatia due to a knee injury.

Gael Monfils has withdrawn from France's Davis Cup semi-final against Croatia with a knee injury. (AAP)

World No.8 Gael Monfils has been ruled out of France's Davis Cup semi-final against Croatia in Zadar because of a knee injury,.

The US Open semi-finalist is replaced by Richard Gasquet, who will play in Friday's singles along with Lucas Pouille.

France were already without the injured Jo-Wilfried Tsonga.

Britain host Argentina in the other semi-final.