Reading's League One play-off hopes suffered a major setback after they were beaten at home by mid-table Lincoln.
Opportunities were few and far between in a goalless first half but Lincoln broke the deadlock in the 65th minute through substitute James Collins.
It was enough to give the Imps a deserved victory against their off-colour hosts.
Prior to kick-off at the SCL Stadium, Reading had lost only once in 15 games and boasted a nine-match unbeaten home record.
Lincoln, undefeated in three outings, had neither play-off nor relegation issues to concern them over the league run-in.
Reading opened strongly, with Imps goalkeeper George Wickens having to be alert in the early exchanges.
Twice Wickens had to claw away goalbound headers, first from Harvey Knibbs and then from Mamadi Camara.
Lincoln gradually forced their way into an increasingly even contest.
Home keeper Joel Pereira had to save smartly at his near post from a well-struck Reeco Hackett effort before turning away a Freddie Draper snapshot.
Reading dominated after the interval but often wasted promising approach work and rarely troubled Wickens.
And Collins, on the pitch only a matter of seconds, made them pay.
He met Hackett's free-kick with an unchallenged and precise header – his first touch of the ball – that evaded the helpless Pereira and ultimately proved to be the winner.
Match report supplied by PA Media.
