Lincoln maintained their promotion push with a 2-0 victory at Mansfield to make it 16 games unbeaten in League One.
Despite their FA Cup glory at Burnley last week, Mansfield have now gone seven league games without a win.
City were the better side in the first half and finally broke through on 43 minutes from the penalty spot after Will Evans had tripped Jack Moylan.
Rob Street’s low penalty just inside the left post just beat the dive of Liam Roberts.
Roberts had earlier produced a fine reaction save to keep out Sonny Bradley’s close-range volley from a free-kick on 18 minutes and Conor McGrandles was not far wide with a low 25-yard effort three minutes later.
Stags came back out on the front foot and George Wickens quickly had to come out to block an Evans finish.
Rhys Oates thought he had won a penalty on 64 minutes as he was flattened by Wickens’ challenge but it was not given.
Street and Bradley both went close with headers from corners in a half of few chances while Louis Reed was inches wide for Stags from 20 yards in the final minute.
But City had a sting in the tail as Dom Jefferies crossed for Tom Bayliss to steer home a close-range volley in the fifth added minute.
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