Neymar marked his first start since January with a fine Coupe de France final goal, but his PSG side lost out on penalties to Rennes.
Neymar marked his first Paris Saint-Germain start since January by scoring a sublime chip in Saturday's Coupe de France final, but suffered disappointment as Rennes stunned the Ligue 1 champions on penalties to deny them a domestic double.
Dinks in sumptuous strike to put PSG two up
PSG were 2-0 up and cruising at the Stade de France after the Brazil forward, who returned from a three-month injury lay-off as a substitute in last Sunday's league win over Monaco, collected Ángel di María's 21st-minute through ball and lifted a delicate effort over goalkeeper Tomás Koubek.
Supplied pass for Alves' opener earlier in first half
Earlier, the 27-year-old had provided the pass from which compatriot Dani Alves volleyed in a sensational opener for the Parisians.
Rennes peg PSG back before winning shoot-out
However, a Presnel Kimpembe own goal shortly before the break was followed by a second-half Mexer strike as Rennes hit back to level the final - and when the teams could not be separated after extra time, Christopher Nkunku's penalty miss gave the underdogs a 6-5 shoot-out victory.
Rennes last lifted the Coupe de France way back in 1971.