Tottenham bounced back from last weekend's FA Cup semi-final defeat to Portsmouth with a hard-earned victory over north London rivals Arsenal in midweek.
It is that lack of consistency that has prevented Spurs making a title push this season, but Ancelotti has already tipped them to be a real force next term.
"Harry Redknapp is doing a very good job at Tottenham," said the Italian. "He did a very good job winning the FA Cup in 2008 at Portsmouth. Tottenham haven't played with continuity, but have played football with very good quality. They are a team that likes to play. They have very good players with a lot of quality. They could challenge next season - they can fight for the title."
Ancelotti promised that Chelsea would take the same attacking mentality to White Hart Lane that saw them defeat Manchester United at Old Trafford.
Chelsea are four points clear of United at the summit and a win would go a long way towards sealing their first title since 2006.
But while United boss Sir Alex Ferguson insists that a draw would be good enough for Chelsea, Ancelotti disagrees.
"I don't think so," added Ancelotti. "A draw wouldn't be a good result.
"We want to maintain a good philosophy against Tottenham and try to win the game. That would be the best thing. I don't know if it will be possible.
"I was surprised at their performance against Arsenal because they reacted well after the Portsmouth defeat and played a strong match.
"We want to put pressure on them immediately. I don't know if it's possible because Tottenham will want to do the same. But that is the right way to get a good result."
Source: PA
Source: PA