Together with Lexus Team SARD teammate Kohei Hirate, Kovalainen came into the final weekend with a 10 points deficit to 2015 champions Tsugio Matsuda and Ronnie Quintarelli in the GT500 class.

But with a second place in Saturday's first race and a first win of the season in the second race, they clinched the title by 13 points over Kazuya Oshima and Andrea Caldarelli, who finished second in the finale.

Matsuda and Quintarelli dropped to third place in the final standings, 20 points adrift of Kovalainen and Hirate, with a seventh place finish.

Over the year, Kovalainen and Hirate claimed four podium finishes in their second season together, which was also the Finn's sophomore year in the Japan-based series.

It marked Kovalainen's first championship win since his World Series by Nissan title victory in 2004, and his first in GT racing, while his Motegi win stands as his first in international motorsport since his Hungarian F1 Grand Prix victory of 2008.

Former Toyota F1 tester Hirate previously won the Super GT title in 2013 alongside Yuji Tachikawa, also in a Lexus.