A knee injury knocked Jo-Wilfried Tsonga, the rising French star who looks like a young Muhammad Ali, out of this weekend’s Davis Cup matches against the U.S., according to news reports. Tsonga will be replaced in the lineup by Arnaud Clement, who most likely will team with Michael Llodra in doubles, leaving the singles to Richard Gasquet and Paul-Henri Mathieu. The individual matchups will be announced tomorrow during the draw ceremony.