Didier Drogba was taken to hospital after suffering a sickening head injury in Chelsea's 3-1 win over Norwich.
The striker was knocked out in a collision with John Ruddy, the visitors' goalkeeper, and was carried off on a stretcher wearing what appeared to be a breathing aid after receiving seven minutes' treatment at Stamford Bridge.
Drogba remained unconscious "for quite some time", manager Andre Villas-Boas said afterwards, revealing the 33 year old had been taken to hospital.
The club later confirmed Drogba had undergone a scan, which showed nothing untoward.
Villas-Boas had no problem with Ruddy's challenge but said of the incident: "It looked pretty nasty.
"He lost consciousness completely on the pitch. I have to be very, very grateful, not only to my players but to the Norwich players and to my medical staff for reacting so quickly to a potentially dangerous situation."
Drogba's injury scare was just one of several dramas in yesterday's game, which was ultimately decided by a controversial penalty.
Its award with 10 minutes remaining sparked a major flashpoint between the benches, with Paul Lambert, the Norwich manager, shoving Chelsea coach Jose Mario Rocha after the latter entered the visitors' technical area to celebrate the spot-kick.
Describing Rocha as "the guy with the stopwatch on his neck", Lambert said: "I don't know who he is but he's flown right into our area. I'm not fluent in Portuguese so if he understands Glaswegian then he might know what I said.
"You don't do that - it's disrespectful."
Villas-Boas hit back, saying: "I know Paul was excited, not only with that. It's difficult to control your own emotions on the bench.
"But I would find it very, very strange if my technical staff would be disrespectful of Norwich and maybe they were just showing some emotions. If Paul can't handle that, I'm sorry - unlucky."
Lambert also took issue with the penalty award, which came after Ruddy brought down Ramires.
Branding referee Mike Jones' decision "harsh", he added of Ramires: "I think he's lost control of the ball. He's actually going to ground before he's got it. But the referee's only got one take on it."
Ruddy was sent off and Lampard scored the penalty to make it 2-1, with substitute Juan Mata sealing the victory on his debut in the closing seconds of what was 11 minutes of stoppage-time.
The scoreline flattered Chelsea with Norwich enjoying as many clear-cut chances before going down to 10 men.
Villas-Boas admitted his side lacked "fluency" in the first half but insisted they dominated the second, even though it saw Grant Holt cancel out Jose Bosingwa's sixth-minute opener after a horrible error from Hilario.
"The 1-1 came against the running of the game," Villas-Boas said. "The impact of the 1-1 on the emotional part of the game is tremendous but, again, I'm very, very happy that the team is able to control their state of mind, to fight back, to show commitment and desire."
He added: "We looked better overall in a 90-minute performance."
Chelsea announced after the game they had signed Ulises Davila, the Mexico Under 20 international, from Chivas Guadalajara.
* Press Association