Eri Hozumi and Makoto Ninomiya's hopes of becoming the first all-Japanese pair to win a Grand Slam doubles title were swamped by a barrage of big hitting from Czech pair Barbora Krejcikova and Katerina Siniakova in Sunday's French Open final.
The sixth seeds won 6-3, 6-3 in just 65 minutes against Hozumi and Ninomiya who had stunned top seeds and Australian Open champions Kristina Mladenovic and Timea Babos in the semi-finals.
For the Czechs, it was their first Slam title.
On Saturday, Japan had enjoyed two title victories at the French Open.
World number one Yui Kamiji won her third Roland Garros women's wheelchair championship with a 2-6, 6-0, 6-2 victory over Diede de Groot of the Netherlands.
It was the sixth Slam singles title for the 24-year-old world number one.
Shingo Kunieda then claimed the men's title, his seventh in Paris and 22nd overall at the majors.
The 34-year-old defeated Argentine second seed Gustavo Fernandez 7-6 (7/5), 6-0.
Final chance: Japan's Eri Hozumi and Makoto Ninomiya in action at Roland Garros on Sunday in the women's doubles final