Kylian Mbappe was sent off in extra-time before Christopher Nkunku missed the crucial effort from the spot to deny PSG a fifth triumph in a row in the competition, putting further pressure on head coach Thomas Tuchel.

The Ligue 1 champion had led 2-0 after just 21 minutes thanks to stunning goals from Dani Alves and Neymar, making his first start since returning from the foot injury suffered in January.

A Presnel Kimpembe own goal and a header from Mexer dragged Rennes back into the contest, and it was Julien Stephan's men who held their nerve in the shootout to win the trophy for the first time since 1971.

Alves took a dreadful free-kick just three minutes before he broke the deadlock in sensational fashion, meeting Neymar's deep corner with an unstoppable volley from the edge of the area.

Eight minutes later, Alves started a quick counter-attack that saw Angel Di Maria play a fine throughball to Neymar, who chipped goalkeeper Tomas Koubek in impudent fashion.

M'Baye Niang hit the post as Rennes threatened a comeback, though, and when Kimpembe turned Hamari Traore's cross into his own net, the Ligue 1 champion suddenly looked shaky.

Koubek made a fine save to keep out another fierce Alves strike, but just as PSG began to take control of proceedings again, Mexer escaped Di Maria at a corner to head home Rennes's equaliser.

Into extra-time, Neymar sent Mbappe through but his effort went behind the waiting Edinson Cavani and struck the base of the right-hand post before rebounding to safety.

Mbappe's frustrating outing reached a nadir 118 minutes in, as he saw red for a poor high challenge on Damien Da Silva at the end of a period of persistent fouls on both sides.

All 11 of the first penalties were converted, before Nkunku sent his effort high over the crossbar to spark wild Rennes celebrations.