The first National Scrabble Championship of the UK was played by high score rules in 1971, and was won by Steven Haskell.
In modern "match play Scrabble" tournaments, players dispute a fixed number of games.
In most major tournaments, for example the World Scrabble Championship and the National Scrabble Championship the players are sorted by number of games won and to break ties between players with the same number of wins, the total of the player's scores minus the total of his opponent's score (known as the spread) is calculated.
Whether the player wins or loses the game, or what his opponent's score is are not a factor.
Thus a player could lose all of their games and still finish in the top half of a tournament with above average scores.