Chelsea boss Graham Potter says Mateo Kovacic did not start against Manchester United because of an ongoing knee problem.
Potter made a first-half change, sending the Croatian midfielder on for defender Marco Cucurella.
“He’s been nursing a knee for all of the season, pretty much,” Potter explained.
“Then you look at the schedule and it’s suddenly games Wednesday and Saturday – it’s impossible for him to start all the games.
‘We’d planned for him to have less time than he has, but things have conspired so he’s been on the pitch.
“We know his quality, but at the same time you also need to understand the player’s situation as well.”
The 1-1 draw at Stamford Bridge left Chelsea fourth in the Premier League, sixth points away from leaders Arsenal.