“One particular common fix would be to split the first two sets to a predetermined script, then play the third set fairly to determine which player progresses,” said Dorward. “I have traded matches where I am convinced that this has happened—bets have been placed on certain games for breaks of serve and correct scores in the opening two sets that have all come in.”
Would say I saw this last week in Sonego's match. Traded bagels before playing the last set properly. Obviously can not say for sure it was a fix but it matches the description of the article which I thought was interesting.