Carlo impressed by 'dangerous' Villa

Carlo Ancelotti has pinpointed in-form Aston Villa as a side with the potential to break up the Premier League's established big four.

Martin O'Neill's Villa side leapfrogged above Arsenal into third place with victory over Sunderland on Tuesday night.

Chelsea remain top of the Premier League but only on goal difference over Manchester United who beat Wolves 3-0. But the Blues have the chance to restore their three-point lead with victory over lowly Portsmouth at Stamford Bridge on Wednesday.

While Chelsea manager Ancelotti is well aware of the threat posed by United, Villa are the team he believes could upset one of the familiar big four - Chelsea, Manchester United, Arsenal and Liverpool - and cement a Champions League spot this season.

"Aston Villa are a very dangerous team," said Ancelotti. "They won against Chelsea and Manchester United. I think Martin O'Neill is doing a fantastic job with this team.

"Maybe we have to pay attention to them because nobody spoke about Aston Villa in the top four but now we have to pay attention to this team. I think Arsenal have to pay attention to them."

Ancelotti's side will be looking for their first win in five games against Portsmouth, who are now led by former Blues boss Avram Grant. Grant returns to Stamford Bridge for the first time since being sacked by the Blues soon after the Champions League final defeat against Manchester United in 2008.

But Chelsea could be without 18-goal Ivory Coast striker Didier Drogba, who hurt his back in training yesterday. Ancelotti revealed that Drogba had to leave their training session after sustaining the injury which now threatens his participation against the struggling south coast side.

It will be a bitter blow for the Blues if Drogba misses out as he was outstanding against Everton - scoring two goals in their 3-3 draw last Saturday.

"We had a problem yesterday morning with Drogba," admitted Ancelotti. "He took a knock on the back and I don't know if he will be able to play tonight."

Chelsea have also been suffering from defensive jitters, with all three Everton goals in their 3-3 draw on Saturday coming from set-pieces. Ancelotti insists he was not angry after that game but does admit to losing his temper with the Chelsea players after their 2-2 draw with APOEL at Stamford Bridge in the Champions League.

"To become angry does not mean you lose control," said Ancelotti. "Sometimes with the team and the players, you have to show your disappointment. It doesn't mean you lose control."

The former AC Milan coach will try to speak with the Italian club's owner, Silvio Berlusconi, in the next few days. Italian Prime Minister Berlusconi suffered a broken nose and teeth from an attack during a rally in Milan's Piazza Duomo earlier this week.

Ancelotti added: "I will try to speak with him in the next few days. It is unbelievable what happened to Mr Berlusconi. I am disappointed but sometimes people lose control."