Chelsea defender Kurt Zouma was on his feet and did not go to hospital after being stretchered from the Pride Park field during his team's 3-1 Capital One Cup victory at Derby County.
Goals from Eden Hazard, Filipe Luis and Andre Schurrle powered Chelsea through to the semifinals, as they saw off a late Derby surge begun by a Craig Bryson goal.
The defender was knocked to the floor after colliding with Petr Cech's protective helmet during a Derby corner kick and received treatment for seven minutes as the first half drew to a close.
Manager Jose Mourinho had good news on the 20-year-old Frenchman.
"He's fine," said Mourinho. "We don't think it's serious. He was dizzy and had some blood in his mouth from a cut."
Paramedics were hurried on to the pitch by Chelsea's medical team with concerned teammates Cesc Fabregas and Cesar Azpilicueta each grabbing the front of the stretcher to speed up the process.
Mourinho said he was unhappy about the speed that assistance arrived on the field, but said he was satisfied by the explanation received. Zouma was already being attended to by club doctor Eva Carneiro.
"The players, their body language, suggested there was some trouble," he said. "They were walking. After that I was informed that this was the direction they have. They can't run."
Mourinho said that Zouma is likely to be fit to play at Stoke City next Monday as Chelsea begin their festive programme of four matches in 11 days.
Striker Didier Drogba pulled up with an ankle injury, and Mourinho confirmed it had swelled up and looked "big".
"I don't think so," Mourinho continued, when asked if the injury would keep the veteran out for long. "He's a strong guy. He wants to play, he wants to help."
"I think it [Zouma's injury] had an effect on the game," said Fabregas, awarded man of the match on returning to Chelsea's team after missing the weekend's Premier League victory over Hull.
The Spaniard was singled out for praise by his manager.
"He's a world champion and he wants to come to Derby in a competition like the League Cup and play," said Mourinho. "This impresses me."
"He's playing so well, what I like especially, more than the quality, is the person, he's a professional."
"I'm enjoying it," said Fabregas who said that Chelsea have the "talent, discipline and courage" to win four trophies this season. They lead the Premier League, remain in both the Champions League and League Cup and begin their FA Cup quest in January against Watford.
"We have a very strong squad, not just the team. Everyone performs really well and we will need everyone until the end of the season if we want to go for everything."
"The important thing is to win Monday, win match by match," said Mourinho, who said he was happy enough to have drawn Paris Saint-Germain in the last-16 Champions League draw made on Monday morning.
"It's an easy flight," he said. "For the supporters, they can go the same day."
Derby manager Steve McClaren said he was "proud" of his players.
"We grew into the game," he said. "We restricted Chelsea to very few chances."
McClaren was irked by the dismissal of defender Jake Buxton for pulling back Loic Remy, which happened as Derby were pushing for an equaliser after Bryson had pulled a goal back.
"I have seen it quite a few times," he said "It was a tough call from the linesman. I've discussed it with him.
"It robbed us of the opportunity in the last 15 minutes when we had the momentum."