Reporting Player

I just wonder if there's anyway I can report a player except for using the post-game reporting system? I've just had a ranked flex game with my friends where we encountered a team of Chinese players. They played better than we did and won the game, which was fine to me, but in the post-game chat, they tried to show their "superiority" by saying something like "white skin trash." I wanted to report them for being toxic and racist, but I accidentally exited the chat...