Monaco midfielder Takumi Minamino scored twice as his side continued their bright start to this season's Champions League league phase with a big victory over winless Red Star Belgrade.
Ex-Liverpool player Minamino beat the offside trap to put his side ahead after 20 minutes.
Red Star's Cherif Ndiaye levelled things from the spot seven minutes later, after he was fouled by Thilo Kehrer.
Breel Embolo restored Monaco's lead deep into first-half stoppage time, then defender Wilfried Singo made it 3-1 with a brilliant strike into the top corner from 30 yards.
Monaco continued their dominance as Embolo next had a goal ruled out for a handball and Maghnes Akliouche hit the post before Minamino added his second in the 70th minute.
Monaco substitute Aleksandr Golovin also struck the post late on, and Akliouche scored his side's fifth in the closing seconds of the game.
Adi Hutter's side, who beat Barcelona in their Champions League opener, have recorded two wins and one draw so far in this season's competition.
Red Star, who face Barcelona next, have lost all three of their league phase matches this season.
Watch highlights of every Champions League game from 22:00 BST on Wednesday on BBC iPlayer and the BBC Sport website and app.
There will also be a Champions League Match of the Day on BBC One on Wednesday, from 22:40 to 00:00.