>>529142128
Why not? 16 players, 4 rounds

1. Round: match 16 players randomly
2. Round: match 8 players with 1-0 record with each other
3. Round: match 4 players with 2-0 record with each other
4. Round: match 2 players with 3-0 record with each other
End result: Exactly one player with 4-0 record, the winner.