The question is pretty pointless and i was surprised it was approved by FlyOrDie moderation.
Here's why.
1.) This question could have simply been asked in the chat lobby and you would have probably gotten a challenge from a player who is up to a competitive game.
2.) You could have challenged another expert level player (yellow colored shield), which is a ranking system is put in place so that we are easily able to differentiate an opponent's level.
3.) Responses on the forum are usually delayed. You will probably not see the person who replied "Yes, i'll play." in the same game room unless a time and place is stated among the two parties.
Therefore, it doesn't really require a forum post.