Real took the lead in the ninth minute through Karim Benzema, but Gaku Shibasaki scored either side of half-time to put Kashima in front.

Ronaldo levelled from the penalty spot on the hour mark after Lucas Vazquez was fouled by Shuto Yamamoto.

The Ballon d'Or winner put his side ahead in extra time after being played through by Benzema, and completed his hat-trick seven minutes later.

Victory gave Real their second Club World Cup and extended their unbeaten run to 37 games in all competitions.

It also means nine of the past 10 winners of the competition have come from Europe.