The 23-year-old defender has struggled to match the performances of his last two seasons during which he was rated as one of the best centre-backs in France.
"We've talked with him and he knows what he needs to do to get back to his best," Ligue1.com quotes him as saying.
"He's a top professional who has a great capacity for self-analysis."
Nkoulou joined Marseille from Monaco in 2011.
Restore Data
| Team | P | W | D | L | F | A | GD | PTS | |
| 1 | Paris Saint-GermainPSG | 12 | 10 | 2 | 0 | 36 | 10 | 26 | 32 |
| 2 | MonacoMonaco | 12 | 8 | 2 | 2 | 21 | 10 | 11 | 26 |
| 3 | Marseille | 12 | 7 | 2 | 3 | 27 | 16 | 11 | 23 |
| 4 | Lille | 12 | 6 | 4 | 2 | 19 | 11 | 8 | 22 |
| 5 | Nice | 12 | 5 | 5 | 2 | 23 | 12 | 11 | 20 |
| 6 | Lyon | 12 | 5 | 4 | 3 | 19 | 16 | 3 | 19 |
| 7 | Auxerre | 12 | 6 | 1 | 5 | 21 | 19 | 2 | 19 |
| 8 | Reims | 12 | 5 | 3 | 4 | 20 | 16 | 4 | 18 |
| 9 | Lens | 12 | 4 | 5 | 3 | 13 | 12 | 1 | 17 |
| 10 | Toulouse | 12 | 4 | 3 | 5 | 13 | 14 | -1 | 15 |
| 11 | StrasbourgStrasbourg | 12 | 3 | 4 | 5 | 21 | 24 | -3 | 13 |
| 12 | Brest | 12 | 4 | 1 | 7 | 16 | 22 | -6 | 13 |
| 13 | Saint-EtienneSt Etienne | 12 | 4 | 1 | 7 | 11 | 25 | -14 | 13 |
| 14 | Le HavreLe Havre | 12 | 4 | 0 | 8 | 10 | 23 | -13 | 12 |
| 15 | Rennes | 12 | 3 | 2 | 7 | 13 | 19 | -6 | 11 |
| 16 | NantesNantes | 12 | 2 | 4 | 6 | 14 | 19 | -5 | 10 |
| 17 | Angers | 12 | 2 | 4 | 6 | 13 | 21 | -8 | 10 |
| 18 | Montpellier HSCMontpellier | 12 | 2 | 1 | 9 | 11 | 32 | -21 | 7 |
| > Ligue 1 Full Table | |||||||||
