Rafael Benitez is favourite to be installed as Chelsea's next manager, but Barcelona’s Pep Guardiola has reportedly emerged as the Blues' No.1 target.
However, Guardiola would not be available until the summer.
Prior to Sunday's news that Chelsea owner Roman Abramovich had sacked Villas-Boas as a result of the club's dismal results in recent weeks, the Sunday Mirror reported that the Russian wants Guardiola to take charge for next season.
Benitez is favourite to be installed as next permanent Chelsea manager with bookmakers Sky Bet, who make the former Liverpool manager 6/5 to replace Villas-Boas.
The Spaniard leads the market ahead of former Blues boss Jose Mourinho (3/1), who is widely expected to return to the Premier League if and when he quits Real Madrid, former England coach Fabio Capello (9/2), and Guardiola (12/1).
Guardiola is out of contract at Camp Nou at the end of the season and is yet to commit his future to Barca. In the past, he has admitted that his time in charge of the Catalans could be coming to an end and it is thought that he will leave the club at the end of next season, if not this summer.
And although the bookmakers on Sunday morning still had him pegged as fourth favourite to succeed AVB, prior to the Portuguese being installed as Chelsea boss last summer, the 41-year-old was believed to be close to making a move to Stamford Bridge.
Benitez is believed to have already been sounded out about taking charge until the end of the season should Villas-Boas be sacked, although his agent recently insisted there had been no official contact.
Manuel Garcia Quilon told reporters: "There is nothing official.
"It's only media speculation and we have not been approached by Chelsea."
However, he refused to rule out his client taking charge at Stamford Bridge, adding: "We would only evaluate that possibility once there is an offer."