updating data in a table after calculated field

[OursVolant]

Hello all and thanks in advance for any reply :-)

My database has 2 tables;

First table is PLAYERS
fields are :
(ID player) and (rate)

Second table is GAMES
fields are :
(ID auto number) (date) (ID player1) (player1 goals) (ID player2) and
(player2 goals)

So far I did manage to build a FORM from the (GAMES table),
I use this form to get the rating of both players (from PLAYERS
table),
then I apply a formula to the rating of each one depending of win,
loss or tie,
then I get a new rating for each player following that game.

(here is the big question)
How can I get the new rating for each player, back into the PLAYERS
table,
then the next time I enter a game record in GAMES table, it calculates
with the new rating of the players

Thanks again for your time
OursVolant