Gianluigi Buffon conceded a penalty as a forgettable first appearance for Paris Saint-Germain ended in a 4-2 loss to third-tier Chambly on Sunday.
The 40-year-old goalkeeper, signed on a free from Juventus, played the first 45 minutes in the behind-closed-doors friendly.
His debut began on a difficult note, giving away an early penalty which set Chambly on their way to a two-goal half-time lead.
PSG's deficit came despite the presence of rumoured Barcelona target Adrien Rabiot, former Real Madrid forward Jese Rodriguez and United States international Timothy Weah in the starting XI.
Teenagers Colin Dagba and Virgiliu Postolachi netted after half-time to provide the Ligue 1 champions with a measure of optimism, although their goals failed to spare head coach Thomas Tuchel from his first defeat at the helm.