French league leader Paris Saint-Germain crumbled under pressure to lose 3-1 at Lens for its first defeat of the season on Sunday as second-place Lens cut the gap to four points and maintained its perfect home record.

PSG's weakness against the counterattack was ruthlessly exposed by Lens. The northern side scored at the start of each half and dominated the midfield battle against a rattled PSG to make it nine straight home victories for coach Franck Haise's side. Lens has the league's best defense with 11 goals allowed in 17 matches, compared to 13 for PSG.

Frustrated PSG coach Christophe Galtier was alarmed by the performance, saying his players did not stick to the game plan.

“I struggled to recognize my team. We lacked solidarity and we got wiped out the more the game went on, leaving them far too much room,” he said. “In fact, we did the opposite of what we should have. We struggled against Lens' pressing, we should have played more long passes to make them defend deeper. Athletically, we were dominated.”

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Haise, meanwhile, celebrated his 100th game in charge by grabbing a microphone and singing a club anthem with the jubilant fans. Closely knit with its supporters, Lens has strong working-class roots from its history as a mining community and is known as Les Sang et Or (The Blood and Gold) for its yellow jersey and red shorts. Lens won its only league title in 1998 and was a close runner-up to Lyon in 2002.

The first goal came in the fifth minute.

Lens used its strong pressing game to win the ball and moved it wide left to Florian Sotoca, whose goal-bound cross was palmed away by goalkeeper Gianluigi Donnarumma only for winger Przemyslaw Frankowski to volley home.

The lead was short-lived as forward Hugo Ekitiké, given a rare start in the absence of Neymar and Lionel Messi, scored from close range three minutes later after Lens failed to deal with a cross from the right.

PSG was without Neymar, through suspension, and World Cup winner Messi, who is returning to training after an extended stay back home in Argentina.

“They are two great players who make the difference but that is not an excuse,” PSG captain Marquinhos said. “We lacked cohesion, efficiency and intensity.”

PSG's weakness against rapid attacks was exposed when midfielder Seko Fofana won the ball near his own penalty area and threaded a 40-meter pass to Loïs Openda. He expertly cut inside defender Marquinhos before slipping the ball under Donnarumma.

PSG conceded just two minutes into the second half as midfielder Fabien Ruiz lost the ball, Openda back-heeled it to forward Alexis Claude-Maurice and he slotted past Donnarumma.

PSG star Kylian Mbappé was kept quiet, with the league's 13-goal top scorer mustering only a speculative shot in the 60th.

Galtier's decision to play Mbappé and Morocco right back Achraf Hakimi this week in back-to-back games so soon after the World Cup appeared to backfire as both looked jaded. Galtier said they will be rested for Friday's French Cup game at Châteauroux.

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OTHER MATCHES

Monaco moved up to fourth place after winning 1-0 at home to Brest, with Russia midfielder Alexandr Golovin scoring in the 54th minute.

Monaco coach Philippe Clement made a bold choice selecting 17-year-old Eliesse Ben Seghir over established striker Wissam Ben Yedder, the club's top scorer for the past three seasons.

“He brought a lot of energy to the team,” Clement said. “What’s important is not a player’s age but what he shows on the field.”

Ben Seghir made a sensational league debut in midweek, coming off the bench to score twice — including an Mbappé-style curling winner — to help Monaco win 3-2 at Auxerre.

Monaco is level on points with third-place Marseille, which plays at Montpellier on Monday.

Lyon lost 1-0 at home to Clermont, with midfielder Muhammed Cham scoring a penalty with three minutes left. The win moved Clermont into ninth place and two points behind Lyon in eighth.

Rock-bottom Angers took a 10th-minute lead through striker Abdallah Sima, but Lorient equalized in the 79th when Sima turned Enzo Le Fée's corner into his own net. Le Fée hit the winner for 2-1 as Lorient moved up to sixth spot.

Toulouse won 2-0 against Ajaccio, with goals from Rafael Ratao and captain Brecht Dejaegere.

Substitute Marcus Coco scored the winner as Nantes beat Auxerre 1-0 to pull clear of the relegation zone.

MONDAY'S GAMES

Rennes needs a home win over Nice to move above Monaco into at least fourth place in the chase for a Europa League spot.

After a narrow 2-1 defeat at PSG, struggling Strasbourg hosts Troyes, and Lille hosts Reims.