Carlo Ancelotti insisted his side are not suffering from title jitters after Chelsea laboured to a 1-0 victory over Bolton at Stamford Bridge.[LNB] Nicolas Anelka's first-half strike, his first in 14 games, sent Chelsea four points clear of Manchester United at the top of the Premier League table[LNB]Bolton boss Owen Coyle criticised referee Lee Probert for failing to give his side two penalties but Ancelotti refused to be drawn into the row.[LNB]Chelsea can now afford to lose one of their four remaining games and still win the title and Ancelotti remains confident his players can keep their nerve.[LNB]"Now the Premier League is in our hands and we have to stay focused and calm," said Ancelotti.[LNB]"We have to play game by game, and we are not interested in the results of the other teams.[LNB]"There was pressure on us to get this result because we needed to improve our position, but I think the players now have very good motivation to finish the season well.[LNB]"It was not an easy game. We knew it wouldn't be, because Bolton came to Stamford Bridge to play their game. They put pressure for all the 90 minutes, a lot of long balls.[LNB]"It was a tough game for us, but I think that Chelsea did a good job and won, which was the most important thing. We were unlucky not to improve the scoreline at the start of the second half, but we needed the three points.[LNB]"We had 21 shots, so we deserved to win. There's no debate about this. It was difficult because, when you're 1-0 up, you have to be careful right to the end. For me, it was a very good performance."[LNB]Ancelotti was not at all interested in Coyle's claim that his side were robbed of two penalties.[LNB]"I don't have a reaction to the penalties," he added.[LNB]"I maintain the same opinion: it's not my job to judge the work of the referees. I never did, even if we were unlucky at their decisions. I didn't see the incidents. I trust in the referee."[LNB]But Coyle insisted that Didier Drogba was guilty of handball in the opening half and that John Terry committed a similar offence in the second period. Referee Probert dismissed both penalty appeals to leave Coyle raging.[LNB]"We didn't need any luck tonight, we only needed the officials to get the big decisions right," fumed Coyle.[LNB]"There were two stonewall penalties out there for handballs.[LNB]"The first one, after 27 minutes when Drogba handballs in the area. I know Drogba is a world-class player, but he could play world-class volley ball for anybody on that evidence.[LNB]"Then there's the second one when John Terry handles it. The assistant referee says it hit his shoulder, but it's a clear penalty.[LNB]"That's not unlucky. The referee has not been helped by his assistants if he's not in a good position to see it. I can accept it if they've not seen it.[LNB]"The first one I don't know about. But as for the second one, the assistant said it hit John Terry's shoulder. That's not happened, so that's a poor decision on his part."