Oct 20 (Reuters) - New head coach Thierry Henry saw his AS Monaco side slump to a sixth Ligue 1 defeat in 10 games as they lost 2-1 away to Strasbourg in his first game in charge on Saturday, with Samuel Grandsir sent off in the second half.

Appointed a week ago following the sacking of Leonardo Jardim, Henry took over a side rooted in the relegation zone with six points from their opening nine league games, as well as two Champions League defeats.

As a player Henry spent five years at Monaco, winning the league in 1997, and though the 41-year-old took an assistant coaching role with the Belgian national team in 2016, Saturday's outing marked his first as a head coach.

Monaco were trying to cancel out an Adrien Thomasson header which goalkeeper Seydou Sy fumbled into his own net in the first half when winger Grandsir was shown a straight red for a dangerous challenge on Anthony Goncalves in the 66th minute.

Henry had already had to replace striker Radamel Falcao, who limped off after 37 minutes.

Monaco had a number of chances from set pieces before Strasbourg's Lebo Mothiba chipped over the advancing Sy six minutes from time. Youri Tielemans pulled a consolation goal back for Monaco from the penalty spot in stoppage time.

Earlier Paris St Germain made it a perfect 10 wins out of 10 with a 5-0 hammering of Amiens at the Parc Des Princes, while Lille beat Dijon 2-1 to stay in second place, eight points behind the leaders.

Marseille can climb past Lyon, who beat Nimes 2-0 on Friday night, and go third with a win away to Nice on Sunday evening.

(Reporting by Philip O'Connor; editing by Tony Lawrence)