In an Xboxlive game with a Matchmaking system, and you enter with one more person that a team can hold, Its a game of roulette on who is on the other team.
GUY 1-"Ok, guys. Theres 5 of us going into a 4v4 playlist. Someone is going to be on the other team."

Later-

Guy 2- "NO! I've fallen prey to that old matchmaking roulette."
by ImperialCody May 20, 2010
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