It is their second Grand Slam title together following their victory in the same event at last year's US Open, when Townsend was also on the losing side.

Errani, 38, reached the Roland Garros women's singles final in 2012 and has completed a career Grand Slam in women's doubles, with five major titles.

She also won Olympic gold in Paris last year playing with compatriot Jasmine Paolini.

Errani is again through to the semi-finals of the women's doubles of this year's French Open with Paolini.

They play Russian duo Mirra Andreeva and Diana Shnaider in a rematch of last year's Olympic final.