RIYADH, Saudi Arabia — Panthalassa led all the way to win the $20 million Saudi Cup by three-quarters of a length on Saturday night, relegating trainer Bob Baffert’s horse, Country Grammer, to second place for the second straight year.

Japan nearly swept the first four places until Country Grammer rallied late on the outside under Frankie Dettori.

Defending champion Emblem Road was sixth.

Sent off at 15-1 odds, Panthalassa ran 1 1/8 miles in 1:50.79 under Yutaka Yoshida. The 6-year-old overcame starting from the No. 1 post. He switched from grass, where he had run 23 of his first 24 races, to dirt for the Saudi Cup.

“You know this is not easy. Japanese racing tries everything to improve and develop. Japanese horse racing has become more international,” winning trainer Yoshito Yahagi said.

The victory, worth $10 million, increased Panthalassa’s career earnings to $14,418,903.

Yahagi had a winner last year when Japanese horses earned four victories on the Saudi Cup card. Japan earned three victories this year.

Taiba, the 8-5 favorite also trained by Baffert, finished eighth in the field of 13.

Dettori and Baffert also took a narrow defeat in the Saudi Cup, when Havnameltdown lost by a head to Commissioner King.