His rated agianst you and others in that tournament would be an average against his opponents the formula is

New Rating = Average Opponents + 400 (w - l) / games played

I believe this goes for 24 games

since his rating is unkown you can not assume a rating for him so an average is the fairest way

Hello, not too long ago I had a situation in a tournament where I lost my first round to an unrated player. I was 2145, and he went on to lose every other game. Then he received a provisional rating of 1700, and the game was rated as if I had lost to a 1700 rated player. This seems extremely illogical to me, to rate a well established player (myself) based on a game against an unrated player, whose provisional rating, we all know, can be prone to wild fluctuations. I brougjt this topic up once before on facebook, and was basically shot down because many of my friends just assummed that it was sour grapes on my part, but in fact I am troubled by this apparent flaw in the rating system. Is there a mathematical reason that games must be rated this way? Has anyone else expressed dissatisfaction with this, and is anyone trying to change it?