Andre Villas-Boas was hired as Chelsea manager on a three-year contract on Wednesday, and vowed to build on the stunning success he achieved at Porto that quickly established him as one of Europe's most sought-after coaches.

The 33-year-old Villas-Boas, who has just two seasons of topflight managerial experience behind him, became the seventh manager in eight years under Chelsea's billionaire Russian owner Roman Abramovich - a day after resigning as coach of the Portuguese champions.

Fresh from guiding Porto to Portuguese and Europa League titles in an unbeaten season, the man often compared to his compatriot and former boss Jose Mourinho will bring some much-needed energy and dynamism to a club that failed to land any silverware last season.

''There is no doubt that the challenge for me is to keep winning,'' Villas-Boas told Chelsea's in-house TV channel. ''I am an individual who has that hunger for success and I want to keep it that way.''

Since Russian billionaire Roman Abramovich bought Chelsea in 2003, the club has enjoyed a trophy-laden period that has harvested three English titles, three FA Cups and two League Cups.

The Champions League - a competition Abramovich is said to be obsessed with - has eluded the Blues and it is success in Europe's premier club competition where Villas-Boas will ultimately be judged.

''Let's reflect on the success of the past six years at this club and what we have achieved, and now what we can achieve in the next six years again,'' he said.

Villas-Boas returns to the London club where he worked as a scout between 2004-07 under Mourinho, who won five major domestic trophies in that time. However, Mourinho and his successors Avram Grant, Luiz Felipe Scolari, Guus Hiddink and Carlo Ancelotti always came up short in the Champions League.

''His ambition, drive and determination matches that of Chelsea and we are confident Andre's leadership of the team will result in greater successes in major domestic and European competitions,'' Chelsea said in a statement.

Chelsea described Villas-Boas as ''one of the most talented young managers in football today'' but the man himself said he would just be a cog in the machine.

''Don't expect something from one man,'' he said. ''Expect us to create a group dynamic of everybody getting together, with the fans getting together, with people getting excited with the motivation that is in and around us.

''In the new way of communicating and the new leadership - this is the most important thing,'' he said. ''It's not about my arrival. It's about the continuous success of this club.''

Villas-Boas succeeds Ancelotti as manager at Stamford Bridge following the Italian coach's sacking on the final day of last season, despite having won the Premier League-FA Cup double the previous year.

Villas-Boas will start work immediately on a reported contract of 5 million pounds ($8 million) a year, with one of his first tasks to decide at what stage the team - featuring a number of aging stars like Frank Lampard, Didier Drogba and John Terry - needs to be dismantled and rebuilt.

He will be familiar with many of the current Chelsea squad following his previous spell at the club.

''Andre will bring his coaching experience back to a club he is already very familiar with, having previously worked here for three years,'' Chelsea said in the statement. ''He has always been highly regarded at Chelsea and everyone here looks forward to welcoming him back and working with him.''

Villas-Boas' contract with Porto was terminated Tuesday after the club received payment of ?15 million ($21.5 million) to trigger his release clause.

With Villas-Boas having never managed in the Champions League, the appointment could be seen as a risk. However, Villas-Boas is so highly rated that he has been dubbed by many as the ''Mini-Mourinho,'' after the current Real Madrid coach who has been one of the most successful managers in Europe in recent years.

''Andre was the outstanding candidate for the job. He has already achieved much in a relatively short space of time,'' Chelsea said.

Comparisons with Mourinho were reinforced last month when Villas-Boas emulated his mentor by winning the Europa League, the second-tier European competition which Mourinho lifted with Porto in 2003 in its UEFA Cup format.

He was previously coach at Portuguese side Academica for a year.

Chelsea came second in the league last season and was eliminated by Manchester United in the semifinals of the Champions League.