Last year's runners-up Lens blew a two-goal lead to lose their Ligue 1 opener 3-2 at Brest on Sunday.
In spite of losing their influential captain Seko Fofana and striker Lois Openda during the summer break, Lens made a dazzling start to the new season with Florian Sotoca and Deiver Machado putting them two up after just 22 minutes.
Brest, however, hit back just before half-time when Romain del Castillo netted the first of his two penalties.
Brest took the reins in the second half and equalised through Kenny Lala in the 56th minute.
The game appeared to be heading for a draw before Lens substitute Adrien Thomasson was sent off in the 82nd minute and five minutes later Mahdi Camara gave away another penalty.
Up stepped Del Castillo to bury his second spot-kick and snatch the points for Brest.
On Saturday, champions Paris Saint-German also got off to a slow start when they were held to a 0-0 draw at home to Lorient.
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