WARSAW - France striker Kylian Mbappe marked his Real Madrid debut with a clinical goal as the European champions outclassed Atalanta 2-0 to win the Super Cup on Wednesday.

Uruguayan Federico Valverde put the European champions ahead after 59 minutes from close range and Mbappe fired the ball into the top corner from Jude Bellingham's pass to double the advantage nine minutes later.

Real clinched a record sixth Super Cup crown to move ahead of Barcelona and AC Milan who have each won the annual match between the Champions League and Europa League winners five times.

"It was a very difficult game," Real manager Carlo Ancelotti told a press conference.

"The second half was much better, we had more space in front and we showed our qualities. In the first half, however, we struggled a lot. Atalanta played really well defensively, and we had difficulty in finding space."

Mbappe, who joined Real in June from Paris St Germain, could have opened the scoring in the 15th minute but his first-time attempt was blocked by the Atalanta defense.

Italy's Atalanta, without injured striker Gianluca Scamacca and midfielder Teun Koopmeiners, showed no fear against their illustrious opponents as they played in their first Super Cup.

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After soaking up Real's initial pressure, Gian Piero Gasperini's side grew increasingly confident and Marten de Roon's deflected shot crashed against the bar.

Atalanta continued to make chances, Ederson shooting just wide from distance before Real keeper Thibaut Courtois saved Ademola Lookman's strike.

Rodrygo missed an excellent chance for Real in first-half stoppage time, sending a low pass from Vinicius Jr. against the bar.

Atalanta continued to press after the break and Mario Pasalic tested Courtois with a header which the Belgian goalkeeper brilliantly denied with his finger tips.

Real broke the deadlock when Valverde converted a precise pass from Vinicius.

They could have doubled their lead through Vinicius following a fine counter-attack and Bellingham wasted two good chances before he set up Mbappe for Real's second, cutting the ball back for the Frenchman to provide a neat finish.

The 25-year-old, who won seven Ligue 1 titles with PSG and Monaco but had never previously won a European club competition, was substituted seven minutes from time.

"Real Madrid are undoubtedly strong. They deserved to win at the end of the game because they opened up, they then had the situations to score an extra goal," Gasperini said.

"As a team we lacked the cynicism of the finals... We had the feeling that with a bit of cynicism, at a certain point, it was even within our reach."

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Real kick off their LaLiga season on Sunday at Copa del Rey finalists Mallorca. Atalanta travel to Lecce for their Serie A season opener on Monday.