Anyone else had this problem?

So I've seen a problem in champ select recently: sometimes one of the players on my team will leave the room, and it'll say so in the chat: "xxx has left the room." But then it takes like 10 seconds for the group to disband. I was okay with this, but it happened at 5 seconds left last game. The group didn't disband, and the player didn't rejoin the game once it started. Riot, please fix this.