Manager Avram Grant hailed Chelsea's 2-0 victory at Newcastle United on Monday and said fatigue was to blame for his side's sluggish first half.
Second-half goals by Michael Ballack and Florent Malouda took Chelsea level with Manchester United on 84 points before the season ends on Sunday. Though United have a far superior goal difference, the title remains up for grabs.
"In the last month we have improved game by game but we were very slow in the first half and the movement was not good," Grant told Sky Sports.
"We then changed the tactics and the second half was one of our best."
Grant said Chelsea's recent schedule of Premier and Champions League commitments was behind the first-half display.
"It's not computers; we are talking about people who played 120 minutes three days before against Liverpool, 90 minutes against Manchester United three days before that and 90 minutes against Liverpool three days before that," he said.
"It was excellent football in these matches with a lot of movement so maybe there was a little bit of tiredness."
Ballack headed Chelsea into the lead after an hour but there were one or two scares before Malouda settled it eight minutes from time.
"Against Wigan (in last month's 1-1 draw) we played fantastic football, we deserved to score eight and they scored. So you always have to be a little careful, even when you are dominating as we were today in the second half 100 percent."
SHOWING CHARACTER
Chelsea finish at home to Bolton Wanderers while United visit Wigan needing only to match the Londoners' result to retain the title.
"I think this is one of the best seasons," Grant said. "Sometimes everything is going well but we showed a lot of character, a lot of other things and not just good football.
"Unfortunately the advantage is with United but it will not be easy in the last game because they need to win."
Newcastle manager Kevin Keegan, who twice lost out in title run-ins to United in his previous spell in charge, said he thought his old rival Alex Ferguson would triumph again.
"I like Avram Grant very much and think this Chelsea side is exceptional," he said. "In any other season I think they would have been worthy champions but I can't see Manchester United slipping up at Wigan."
He was less enthusiastic about his own team's prospects, however, saying the club he rejoined in January had no chance of challenging at the top next year after what is likely to be a 12th-placed finish this season.
"I just think 'what have I got to do next year to get near them?' and the answer is that there is nothing I can do at all, and the fans need to know that," Keegan said.
"I haven't got enough money. Chelsea can keep spending and we won't be able to get those players so I'm going to soldier on with the ones I've got, maybe add one or two. It is frustrating and I'm sure I'm not the only manager who feels like that.
"Maybe the owner here thinks we can bridge that gap but we can't."
