The result also keeps the Ligue 1 title race alive with second-placed Lens the only team that can still pip Paris Saint-Germain to the trophy.

The 16-year-old substitute Mesloub picked up a loose ball in the box with his first touch in the 79th minute and fired home with his second to break the deadlock on his Ligue 1 debut.

Lens are now guaranteed a top-three finish in Ligue 1 after moving nine points clear of fourth-placed Lille, with both teams having two matches remaining.

The top three teams in Ligue 1 qualify automatically for the Champions League league phase, while the fourth-placed side heads into the qualifying rounds.

Lens, whose budget is not even a 10th of Champions League finalists PSG, are still to play the Parisians who lead them by three points and have a game in hand.

Following the win, the sell-out 38,000 crowd at Lens' Stade Bollaert stayed behind for extravagant celebrations, with the players heralded one at a time on a spotlit centre-circle with fireworks flaming.

Stopping PSG remains an outside chance, but Lens are also eyeing silverware in the French Cup, with the final against Nice on May 22.

Lens, the 1998 French champions, were the surprise package earlier in the season as they reached the winter break top of the table.

Lens had three goals ruled out for offside or handball Friday as Nantes held them at bay largely thanks to goalkeeper Anthony Lopes.

Nantes are now guaranteed to finish in the bottom two and will be relegated from Ligue 1.

Club great Vahid Halilhodzic took over as the third coach of their season in March but could not save the Canaries.

PSG play Brest at home on Sunday but the Lens win has prevented them from mathematically wrapping up a fifth straight title this weekend.

However, their far superior goal difference means victory would all but wrap up top spot.

Luis Enrique's men will face Arsenal in the Champions League final on May 30 after beating Bayern Munich 6-5 on aggregate in the semi-finals.

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