Jo-Wilfried Tsonga may have to miss Wimbledon after injuring a finger during his 7-6 (3), 3-6, 7-6 (5) third-round loss to Ivan Dodig at Queen's Club on Thursday.
Last year, the charismatic Frenchman lost to Andy Murray in the Queen's final and upset Roger Federer in the Wimbledon quarterfinals.
"I think it's serious," Tsonga said. "I just fell down. That's it. I didn't do, you know, an exam for the moment, but it sounds very bad. I felt like I broke something or I stretched, you know, a lot of ligaments, I would say."
Dodig will play Sam Querrey, who kept on track to reach his second final at the pre-Wimbledon event by upsetting eighth-seeded Frenchman Julien Benneteau 6-3, 3-6, 6-3.
Querrey, who beat fellow American Mardy Fish in the 2010 final, earned a decisive break to lead 5-3 in the final set and served out the match to love.
"I'm feeling really good," said Querrey, who was still on the comeback trail after elbow surgery one year ago. "I have been feeling better every week this year, and my serve is feeling great. I've only dropped serve once so far in three matches.
"Return game is feeling good. Yeah, that's the first time I have won three matches in a row in a while. Just feeling really confident."
Nicolas Mahut failed to follow up his Wednesday victory over Murray when he was ousted 7-6 (3), 6-4 by Bulgaria's Grigor Dimitrov.
Ninth-seeded Kevin Anderson of South Africa fought off a strong challenge from fifth-seeded Spaniard Feliciano Lopez to win 7-6 (10), 7-6 (7).