PARIS, Feb 27 (Reuters) - A strike deep in extra time by substitute Sidi Keita gave Racing Lens a 5-4 victory at Le Mans in a thrilling French League Cup semi-final on Wednesday.

A shootout was looming when Mali midfielder Keita scored the winner from the edge of the box 118 minutes into an action-packed tie played under driving rain.

Northerners Lens will meet fellow Ligue 1 strugglers Paris St Germain in the final on March 29 at the Stade de France, with the winners qualifying for the UEFA Cup.

Lens twice fought from a goal down in a lively first half before squandering a 4-2 lead in the second.

Ivorian forward Gervinho put Le Mans ahead from close range on 22 minutes but the visitors levelled 15 minutes later, with Le Mans’s Brazilian striker Tulio deflecting a free kick into his own net.

Defender Hassan Yebda restored the home side’s lead shortly before halftime, only for Lens to level again a few seconds later with a superb volley from striker Loic Remy.

Lens looked to be cruising after second-half goals from Ivory Coast forward Aruna Dindane and midfielder Olivier Monterrubio put them 4-2 up but Le Mans recovered with goals in quick succession from Japan midfielder Daisuke Matsui and Tulio.

Extra time was needed and there were chances at both ends before Keita sent Lens through.

Twice League Cup winners PSG beat Auxerre 3-2 in the other semi-final at Parc des Princes on Tuesday.