Czech Republic's Siniakova, a veteran in the format with 11 Grand Slam titles in women's doubles, has now won three majors with American Townsend.
Siniakova and Townsend win French Open doubles title for third major together
Katerina Siniakova and Taylor Townsend powered their way to the first French Open triumph together, beating second seeds Anna Danilina and Aleksandra Krunic 6-2, 7-5 in Sunday's doubles final.