Neymar appeared to be in tears as left the field on a stretcher after suffering an injury in Paris Saint-Germain's 1-0 loss to Lyon on Sunday night.
Neymar was carried off the pitch seven minutes into stoppage time with a possible ankle injury following a poor tackle from Thiago Mendes.
PSG have not confirmed the extent of the Brazil international's injury.
It is not the first injury for Neymar since signing for PSG. The 28-year-old has fractured his metatarsal twice since arriving in August 2017, and missed the 2019 Copa America after rupturing his ankle ligaments.
Mendes was sent off for the challenge but it did not affect the result as PSG dropped down to third in Ligue 1 after Tino Kadewere's goal earned the visitors victory.
The French champions were never in the mix as they surrendered top spot in Ligue 1 to Lille, who claimed a 2-1 win at home against Girondins de Bordeaux earlier.
Lille have 29 points from 14 games, leading second-placed Lyon on goal difference with PSG on 28 points after their fourth defeat of the season.
Olympique de Marseille are fourth on 27 points with two games in hand, in a tight top five separated by three points.
Champions League last 16 draw
The Champions League last 16 draw takes place on Monday - who could Liverpool, Manchester City and Chelsea face?
The draw will take place at 11am on Monday, December 14 in Nyon. You will be able to follow it across Sky Sports' platforms.
What is the draw format?
There will be two seeding pots: one consisting of the eight group winners and the other of the eight runners-up.
No team can at this stage play a club from their own association - meaning no all-Premier League clashes just yet - and no side can play a team from their previous group.
The ties will take place over two legs, with seeded group winners playing away in the first legs and at home in the return matches.
Who's in which pot?
- Bayern Munich
- Borussia Dortmund
- Manchester City
- Real Madrid
- RB Leipzig
Who could Premier League sides face?
Chelsea: Atalanta, Atletico, Barcelona, Lazio, RB Leipzig, Mönchengladbach, Porto.
Liverpool: Atletico, Barcelona, Lazio, RB Leipzig, Monchengladbach, Porto, Sevilla.
Manchester City: Atalanta, Atletico, Barcelona, Lazio, RB Leipzig, Monchengladbach, Sevilla.
When will the games be played?
February 15/16: Round of 16 first legs
March 16/17: Round of 16 second legs
What are the other key dates?
April 6/14, 2021: Quarter-finals
April 17 & May 5, 2021: Semi-finals
May 29, 2021: Final (Istanbul)