Celtic became the latest club to stumble in the race for the Scottish Premiership title as struggling Dundee United beat them at Tannadice for the second time this season.
It is the first time United have achieved such a feat in 35 years, and goes some way to alleviating fears they could get sucked into a relegation play-off battle.
United captain Will Ferry got the first goal, stabbing in from close range on a pitch that was heavily criticised for its sandy, bobbly surface.
Emmanuel Agyei, a January signing from FC Ashdod in Israel, scored the unlikely second, drilling in from outside the box to double the hosts’ advantage.
Celtic pushed for a way to get back into the game, but United proved more stable at the back than they did last week in their last collapse against neighbours Dundee.
It was a deserved victory for Jim Goodwin’s men, too.
Although Celtic dominated possession, United had 18 shots – the most the Glasgow club have faced in the league this season – as they peppered the opposition in a surprisingly offensive performance.
Martin O’Neill’s side now trail league Hearts by five points, and second-placed Rangers by two.
As well as claiming another famous scalp, United keep their slim hopes of a top-six finish alive. They are six points behind Falkirk, with two games to play before the split.