Avram Grant, the Chelsea manager, is refusing to rule Arsenal out of the Premier League title race despite last Sunday's 2-1 victory at Stamford Bridge.

Chelsea, who host Middlesbrough on Sunday, remain determined to cement their position behind league leaders Manchester United. However, Grant is not expecting an easy ride after his preparations were disrupted by injury to John Terry and illness to Frank Lampard, his England team-mate.

Lampard has yet to train since returning from international duty but Terry should be fit to face Gareth Southgate's side after overcoming a hamstring problem.

"We might drop points on the way," Grant said. "We need to go game by game. Middlesbrough drew at Arsenal last time, so we need to do our job. It won't be easy. But I don't think Arsenal are out of the race.

"You need to keep your players focused all the time, especially now when you're coming up to the last games. We've done a good job up to now. We were many points behind Arsenal and now we're above them. But they're still in the race. That's my opinion. Not even one team will take all the points.

"Frank Lampard is not feeling so well. He didn't train today but we'll see tomorrow. John Terry trained and I think he'll be okay. We have a game every three days for the next few weeks. We're not just thinking about the next game, but other aspects like physical condition. We have to think like that."

Grant was criticised by the Chelsea supporters during the victory over Arsenal for taking off Michael Ballack and Claude Makelele and replacing them with Juliano Belletti and Nicolas Anelka.

The crowd chanted 'you don't know what you're doing' as Ballack stormed down the tunnel, clearly unhappy at the decision.

However, Grant insists he has no problem with either Ballack or the reaction of the supporters.

"People like to look at the negatives," he said. "Many, many supporters of Chelsea support the club and even support me. If others think otherwise, it doesn't affect me. I have to do my job. I do the tactical side, what I have to do in the condition of the players. I don't hear any other noises. I think I need to do my job, not pay attention to things from outside.

"You do what you think can win you the game. Even Makelele was playing well last week but we needed to change things to win the game.

"That's what happens. The players respect it. If they had a problem, I'd take care of it. It's inside the club (with Ballack's reaction). If there is a problem, I'll deal with it."