Thomas Tuchel expects Mateo Kovacic to miss Saturday's FA Cup final after Dan James' reckless challenge in Chelsea's 3-0 win at Leeds.
Kovacic was forced off in the 30th minute with an ankle injury, shortly after James had been shown a straight red card for his high tackle on the Croatia midfielder.
Chelsea cruised to victory and edged Leeds deeper into the relegation mire through Mason Mount's early opener and second-half goals from Christian Pulisic and Romelu Lukaku.
But boss Tuchel said the satisfaction of his side's timely return to form before they face Liverpool at Wembley had been tempered by Kovacic's likely absence.
Tuchel, whose side halted a three-game winless run to move four points clear of Arsenal in third place, said: "He has a swollen ankle and is in a lot of pain.
"For me, like I say, I'm not a doctor and we need to wait for the examinations, but's very unlikely that he can play. It's absolutely bad news for us on our perfect evening.
"If he misses it I'm very disappointed because he was a clear starter."
James is the second Leeds player to be shown a straight red card for a rash challenge in as many matches following team-mate Luke Ayling's dismissal in Sunday's defeat at Arsenal.
"I did not see the challenge live, I was focused on something else," Tuchel said. "I saw it from a distance on the iPad and I'm not good at looking at these situations because it hurts me physically to watch it."
Chelsea had dropped 10 points in their previous five matches, but made light work of victory at troubled Leeds, which edges the Blues closer to a Champions League berth.
Tuchel added: "I felt the team were very calm, very determined and very focused before the match and they delivered a performance to which we got used to over so many weeks.
"I'm very happy and it was necessary of course, given our situation and not only because we arrive now for a big match, but it's very good to arrive for a match like Saturday with a calm mind."