Los Blancos, who tasted victory at Morocco 2014, were made to work hard for their world title by a spirited Kashima. After Karim Benzema opened the scoring on nine minutes, a Gaku Shibasaki double fired the Asian side into a dramatic second-half lead.
In the first competitive meeting between the two sides, the UEFA Champions League winners took an early lead through Benzema. Luka Modric launched a powerful half-volley from the edge of the area that goalkeeper Hitoshi Sogahata parried into the path of the French forward, who showed natural instinct to latch onto the ball and convert from close range to record his second goal of the tournament.
A goal down, Kashima - spurred on by their vocal supporters clad in red and black - replied with an effort through Shoma Doi, who had a shot blocked by goalkeeper Keylor Navas soon after.
Kashima goalkeeper Hitoshi Sogahata impressed in the first-half, pulling off a stunning one-handed stop to deny a low drive from Benzema, before stopping Modric's curling effort on 37 minutes.
Despite Los Blancos' dominance, Kashima continued to pass the ball elegantly and, with their first clear-cut chance, they grabbed an equaliser before the break. A Doi cross found Shibasaki in the centre of the area who showed great composure to control the ball, beat his marker and fire past Navas to send the host fans into the raptures.
Kashima kept a strong, organised shape in the second half and valiantly took the lead through Shibasaki's 52nd-minute strike. The midfielder showed great technique to beat several defenders before tucking his left-footed effort from the edge of the D into the bottom corner, grabbing his second of the game.
The J.League champions' lead was short-lived, however, when Ronaldo converted a penalty on the hour-mark after Shuto Yamamoto brought down Lucas Vazquez inside the area. Ronaldo went close almost immediately after the restart after winning the ball from Naomichi Ueda and charging towards goal; his effort saved by Sogahata.
Hosts Kashima began to up the tempo as the second half progressed, with a wonderful left-footed strike from Fabricio being tipped over the bar by Navas. The J.League side then came close to bagging a dramatic winner in second-half injury time when Endo received the ball in space inside the area, but the midfielder shot wide of the mark.
As extra-time followed, Ronaldo fired Real into the lead on 96 minutes after receiving a well-worked through-ball from Benzema and completed his hat-trick soon after, latching onto Toni Kroos' pass to convert from close range and secure the Spanish giants the title.
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