The first managerial meeting between former team-mates Thierry Henry and Patrick Vieira ended level as Henry's Monaco side drew with Vieira's Nice.
Allan Saint-Maximin put Nice ahead after a mistake from Youssef Ait Bennasser, but the visitors had Ihsan Sacko sent off just before half-time.
Monaco made the extra man count within five minutes of the restart as Benoit Badiashile's header made it 1-1.
Saint-Maximin had a penalty saved and Monaco's Radamel Falcao hit the post.
Vieira won the Premier League three times with Arsenal and Henry twice, with both men instrumental in their 2003-04 season when the 'Invincibles' won the title without losing a league match.
The pair were also international team-mates, helping France win the World Cup in 1998 and the European Championship in 2000.
Vieira, 42, had a two-year spell in charge of Major League Soccer side New York City before taking over at Nice in June 2018, with Henry becoming Monaco boss, his first managerial role, in October.
Another former Arsenal man, Cesc Fabregas, was one of four Monaco players ineligible for the game having joined since the transfer window opened. The match was rescheduled from December and Ligue 1 rules state only players registered for the initial fixture date can take part.
There was no Mario Balotelli in the Nice squad as he continues to be linked with a move to Marseille.
The result leaves Monaco one off the bottom of the division, while Nice are up to sixth.
Both sides will feel they could have won the game, though, with Monaco playing the whole second half with a man more and Nice wasting their spot-kick in the 77th minute.
VAR was used for both incidents, with referee Benoit Bastien utilising the video technology before showing Sacko a red card after a high challenge on Benjamin Henrichs.
He then used it again to confirm Badiashile's trip on Youcef Atal in the box and the award of the penalty, which Diego Benaglio saved from Saint-Maximin.