Lincoln held promotion-chasing Derby to a 1-1 draw at Pride Park despite Ben House’s red card.
Olamide Shodipo fired Lincoln into a shock lead just before the break, but Conor Hourihane equalised after House’s 55th-minute dismissal.
The visitors almost stunned Derby in the fifth minute when Jack Diamond rattled a post and they hustled the home side into errors in the opening half-hour.
Derby’s Korey Smith saw a shot blocked but Lincoln deservedly went ahead in the 43rd minute when Shodipo pounced after Joe Wildsmith saved from Lewis Montsma.
Diamond broke away after the break but his finish lacked the power to trouble Wildsmith
House received a second yellow for a late challenge on David McGoldrick.
And Derby capitalised by levelling in the 69th minute when McGoldrick’s shot fell to Hourihane, who fired home from close range.
Diamond almost caught Derby on the break and McGoldrick was denied by Carl Rushworth before Louie Sibley struck the bar.
Derby thought they had won it in stoppage time when McGoldrick headed in at the back post but he was offside.
