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Allegri's contract is set to expire in June 2020 and he has been linked with the top jobs at both Real Madrid and Manchester United - two clubs whose managerial situation for 2019-2020 remains unclear.

Juve's victory in the Supercoppa Italiana in January earned Allegri his 10th piece of silverware since taking charge in 2014 and he has won Serie A in each of his four campaigns at the helm.

But Allegri could not give any assurances that his tenure would last beyond this season, which sees the Bianconeri 11 points clear of Napoli at the summit.

"Nothing is certain," he said. "I've been fine here at Juventus for five years and I'm happy. I have a contract and I am happy at Juventus.

"I am focused on the present, on our targets for this season. We've won the Supercoppa, now we have to win Serie A and the Champions League."

Juve face Frosinone in Serie A on Friday but Allegri rejected any suggestion he could rest key players ahead of the first leg of a Champions League last-16 tie against Atletico Madrid next Wednesday.

"[Cristiano] Ronaldo will play, he's always played and he will play tomorrow," explained Allegri. "You are obsessed by the Champions League.

"Today is Thursday, there is almost one week before the game. We need to win to give a boost for the Serie A title and the Champions League as well."

Asked about Juve's acquisition of Aaron Ramsey, who will arrive in Turin when his Arsenal contract expires at the end of the season, Allegri said: "I have to coach him [before offering a proper opinion].

"He is a great player but I want to coach him first before saying something. We'll speak about the new players in the summer or next season."