TURIN • Juventus have never before overturned a two-goal deficit at home in European competition, but then they never had Cristiano Ronaldo leading their attack.

If the aim of buying the five-time World Player of the Year for €100 million (S$153 million) was to make a difference on the biggest Champions League nights, it certainly paid off on Tuesday.

The 34-year-old got his eighth Champions League hat-trick - the joint-highest in the competition with Lionel Messi - as Juventus overturned a 2-0 first-leg deficit against Atletico Madrid with a 3-0 victory to reach the quarter-finals.

Afterwards, Ronaldo declared "that was why Juventus brought me here, to help on magical nights like this".

He said: "In the history of Juve, there was never a comeback like this. I do my job and I'm very happy.

"Atletico are a really tough team to face, but we are strong too and proved we deserved to go through.

"It was meant to be a special night and it was, not just for my goals but also for the attitude we showed. That is the sort of mentality you need to win the Champions League."

While Ronaldo had carried on where he left off, plundering 19 goals in Serie A, his domestic form as the second-highest scorer in the Italian league had not translated to the European stage, with only one strike this term before the Allianz Stadium meeting.

Atletico, who had not conceded a goal in their previous four Champions League games, had packed their defence in the belief they could shut him out again.

But the LaLiga side are Ronaldo's favourite opponents - having scoring 22 goals against them in a nine-year spell with Real Madrid.

His coach Massimiliano Allegri had warned "it would have been weird for him to finish the Champions League with only one goal".

And after adding another three - his fourth treble against Atletico - to that tally, the competition's all-time top scorer with 124 goals goaded their fans, who had barracked him in the reverse game, by mimicking Diego Simeone's crotch-grabbing celebration.

The Argentinian coach, whose negative tactics backfired as they failed to muster a single shot on target, brushed off the taunting as the forward just "showing his character" before admitting his side could not handle the "best in the world".

Pundits agreed with his assessment, with former England striker Gary Lineker claiming Ronaldo, scorer of two towering headers and a late penalty, was "the best header of a ball I've seen".

Former Manchester United teammate Rio Ferdinand hailed him on BT Sport as "a living football god".

He said: "This is against an Atletico Madrid team who are renowned for having an unbelievable defence."

Former Manchester City defender Joleon Lescott added: "He's up there, athletically, he's ridiculous. He loves it, to score goals in any competition.

"Even if you're 2-0 up, you don't want to be facing this guy."

The Spanish press joined in the chorus of lamentation, with Marca questioning why Real "gave away a legend".

It added: "We just saw that Ronaldo is priceless. Letting him go was a historic error, he was worth a billion.

"Madrid should never have let a player like this escape, when he had a contract, and was one of the patrons of the four Champions League wins."

AGENCE FRANCE-PRESSE, REUTERS, THE GUARDIAN