Wimbledon surprisingly completed the double over in-form Reading to put a major dent in the Royals' play-off push.
Without 16-goal striker David Connolly the Dons may have been pleased to settle for a point before kick-off but they thoroughly deserved their victory.
In a ground that resembles a ghost town, the Royals were unable to play any of the exciting flowing football that has won them so many plaudits in recent weeks.
Damien Francis scored the first goal in the 31st minute when he slid the ball past the exposed Marcus Hahnemann. It silenced the large Reading following and was a sign of things to come.
Reading's attacks were too often ended by the offside flag while Andy Hughes' afternoon almost ended in spectacular fashion.
The crazy character careered off the park behind the Wimbledon goal and put a leg straight through a McDonalds advertising hoarding. Initial fear that gripped the stadium soon passed when it emerged Hughes had escaped unscathed.
The Dons almost doubled their lead when Mark Williams' looping header was cleared off the line by left-back Nicky Shorey. Out-of-sorts Luke Chadwick, who this week celebrated the birth of his first child, was on hand to scoop the ball clear.
Reading, from being almost two goals down, almost snatched an immediate equaliser.
Steve Sidwell, who had already brought a good diving save from Kelvin Davis, was put clear as Nicky Forster stabbed a pass to him just five yards out. Somehow the ball got entangled in his feet and the defence recovered to scramble the ball clear.
Reading floundered in the second half with ineffectual build-ups as Wimbledon controlled the game.
Neil Shipperley almost scored Wimbledon's second goal in the 71st minute. He drove a free kick against the Royals wall and drove the rebound beyond the keeper but it smashed off the post and to safety.
Forster almost snatched an equaliser when he fired a shot past Davis only to see it flash just wide.
Wimbledon finally scored a deserved second goal in the 85th minute. Patrick Agyemang and Jermaine Darlington set up Alex Tapp who rocketed a shot into the net to secure a comprehensive victory. The scoreline could have been even wider had the Dons taken any one of their numerous late chances.
It was a reality check for Reading who had begun to murmur of challenging the top two. Now they must concentrate on making sure a Play-Off place is theirs.