Paul Heckingbottom puts Sheffield United on injury alert after voicing grounds for concern

With a 3-1 win over Stoke City extending the gap to third in the Championship to 11 points, complacency is the biggest threat to promotion.

But in-form striker Ndiaye hobbling off with an injury after scoring his first goal since early November was a worry too. And with Enda Stevens and George Baldock missing the game with muscle strains picked up in training, Heckingbottom is anxious to ensure his club does not make its own problems.

The Blades had a new pitch with undersoil heating laid last year but it is not ready to use and Heckingbottom is worried about the problems a sub-standard surface could cause.

"The turn in the weather has laid down a challenge to the medical team and sports science team to come up with a plan to help us protect our players," he said.

"Knowing this league, this time of season and how the training pitches affected us last year when they went, we want to guard against it.

"George and Enda have picked up muscle injuries (in training) and this is what we've got to guard against.

"At the start of the season we had the twists, the contacts, the breaks. We couldn't do much about it but it put a massive strain on our squad.

"I need to manage myself because I know I'll get frustrated, angry and disappointed whether that's over an injury I feel is avoidable or having to change the training programme.

"It (the pitch the team has trained on so far this season) is not fit for purpose. At the start of the season with plenty of grass on, it's rock hard and a little bit bobbly but fine. Now the weather's turned it's slippy, it's boggy, it can have puddles on it.

"We can go on the artificial (pitch) or indoors but we've picked up injuries there."

As for when the new pitch will be ready, Heckingbottom says nature just has to take its course.

"We've got the undersoil heating on," he said. "It's just a case of the grass growing up and more importantly down and binding the surface to be firmer and more playable.

"If we're doing things unopposed on it, it's fantastic moving the ball but for twisting, turning and checking, we don't trust it enough yet."