Livingston 2 - 0 Celtic
Goals from Scott Robinson and Lyndon Tykes have ended Celtic's recent unbeaten run of 11 matches without defeat, and handed the incentive to Steven Gerrard's Rangers side to take poll position, when they face Hamilton Academical at Ibrox at 15:00.
Having dropped points for the first time last weekend away to Hibernian, Neil Lennon's side now head into the international break with just one point from six in the league and suddenly the league shows sign of opening up into one that is of a genuinely competitive nature.
A red card for Ryan Christie after 26 minutes was never going to help matters, but it was a deserved victory for Gary Holt's side and at 2-0 down, Celtic never really looked like they were going to get back into the game, creating few real chances.
Robinson put the home side 1-0 up early in the second half with a fine strike. Robbie Crawford played Robinson through with a neat pass with Robinson placing the ball out of Fraser Forster's reach.
Then on 73 minutes, a long ball put Dykes through, and an expert lob from the forward over Forster, meant Celtic were out of reach and condemned to their first defeat of the season.