Derby County boss Steve McClaren says he must protect George Thorne after the midfielder was replaced in Tuesday's 2-0 win against Charlton.
The former West Brom man, 22, was playing just his second game since returning from a serious knee injury.
He was also substituted in Saturday's win over Sheffield Wednesday.
"It's just a couple of bangs he's got, but we need to protect him because you saw in that first hour how vital he is for us," McClaren told BBC Radio Derby.
|Derby's seven-match unbeaten league run|
|27 Jan: 2-0 W v Blackburn (H)||31 Jan: 2-0 W v Cardiff (A)|
|7 Feb: 4-1 W v Bolton (H)||10 Feb: 2-2 D v Bournemouth (A)|
|17 Feb: 3-3 D v Rotherham (A)||21 Feb: 3-2 W v Sheffield Wednesday (H)|
|24 Feb: 2-0 W v Charlton (H)|
McClaren also said he will need to fully utilise his squad if Derby are to maintain their lead at the top of the Championship table.
The Rams have played six games in the last 18 days and face two more games in the next week.
"We are looking at energy now," McClaren said.
"We've played Saturday, Tuesday, Saturday, Tuesday and we've still got another couple to go. We need the squad now and we'll have a look at them on Thursday and get them recovered."
Despite the busy schedule, Derby extended their unbeaten run in the league to seven games thanks to two goals in the opening 17 minutes from Jeff Hendrick and Jesse Lingard.
"We said that it was important to start well and we started aggressive and played some great football," said McClaren.
"They were great goals and then we controlled the game from then on."