HOW does round to round matchmaking work?!

Yesterday I got forced into 4th, by being placed against the same guy twice in a row in a 4 way contest. He was the 1 I couldn't beat. That was an even 2v2 situation.

I just got forced from a 2nd to 3rd, by fighting the same guy THREE times in a row. And losing all 3. I could beat the 1 other guy left. This was even in the first fight, then became a 3 way contest for the final 2 rounds.