Kylian Mbappe's brother Ethan haunted his former club Paris Saint-Germain as he came off the bench to grab a late leveller for Lille in Ligue 1 on Sunday, while Lyon went down to a surprise 2-1 defeat at home to Toulouse.
The 1-1 draw at Lille's Stade Pierre-Mauroy was, however, enough for injury-plagued PSG to go one point clear at the top of the French league.
A much-changed PSG side made the trip north and substitute Nuno Mendes's sublime second-half free-kick looked to have secured all three points for the reigning champions until 18-year-old Mbappe had the last laugh.
"We prioritised the players' health... It's been a difficult week. After the match in Barcelona (in the Champions League), we're feeling the fatigue," said PSG coach Luis Enrique of his starting XI.
A first half short on goalscoring opportunities culminated in Bradley Barcola passing up a gilt-edged chance to break the deadlock for PSG as he raced through on goal from distance but fluffed his finish.
The hosts started the second period the brighter with 39-year-old Olivier Giroud launching himself at an ambitious overhead kick before Nabil Bentaleb fired into Lucas Chevalier's gloves.
Lee Kang-in and Barcola riposted for PSG as the encounter started to become less cagey.
Luis Enrique made a slew of changes on the hour and was rewarded six minutes later as usual first-choice left-back Mendes whipped a fantastic free-kick into the top corner from 30 yards.
Mbappe then entered the field of play under the watchful eye of his older brother Kylian, now of Real Madrid and who was up in the stands, with eight minutes remaining.
Achraf Hakimi, also off the bench, could have put the match beyond Lille in the 83rd minute but fired wide when well-positioned.
But the headlines went to Mbappe, who two minutes later cut inside on his left foot and fired a shot through the legs of Lucas Beraldo, which flashed beyond the unsighted Chevalier.
"Ethan has character, good self-confidence, and also qualities for the highest level," said Lille boss Bruno Genesio.
Lille trail PSG by five points in seventh spot.
'CRUEL RESULT'
New arrival Emersonn opened his account for Lyon with a brace, including nodding in a 96th-minute winner, as Toulouse fought back to beat Lyon 2-1.
Paulo Fonseca's side went into the weekend's action level on points with PSG at the top of the table but now find themselves fourth after being sucker-punched by Toulouse.
Lyon looked set to go provisionally clear at the top when Malick Fofana put the hosts ahead on 24 minutes.
Brazilian forward Emersonn entered the fray off the bench inside the final 20 minutes to flip the game on its head and bring Toulouse up to ninth on 10 points.
The 21-year-old summer signing from Turkish side Goztepe scored his first for Toulouse in the 87th minute with a deflected effort.
The winner came in the sixth minute of injury time as Emersonn rose highest to glance home a corner.
Lyon assistant coach Jorge Maciel said it was "a cruel but not surprising result".
"It's not enough... We can never be satisfied with a 1-0 lead. We can't take our foot off the gas and give our opponents opportunities," the Portuguese added.
Elsewhere, Cote d'Azur rivals Monaco and Nice played out an entertaining 2-2 draw in the principality.
Sofiane Diop gave the 12th-placed visitors the lead on 29 minutes, before Nice went down to 10 men five minutes later as Ali Abdi saw red for two bookable offences.
Diop nonetheless doubled Nice's lead in the 42nd minute from the penalty spot but the fifth-placed hosts fought back through two Ansu Fati spot-kicks to finish honours even.
Strasbourg thumped 17th-placed Angers 5-0 to go third, level on 15 points with second-placed Marseille and Lyon.
Rennes were held to a 2-2 draw at Le Havre, despite being two goals ahead inside the opening half-hour.
