Lincoln began life without the Cowleys in underwhelming fashion with 1-0 defeat to Bristol Rovers at Sincil Bank.
A scrappy game was decided by Jonson Clarke-Harris' 66th-minute penalty midway through the second half, given after Neal Eardley was adjudged to have fouled Tom Nichols.
In the first game since management duo Danny and Nicky Cowley left for Huddersfield, the Imps had a huge shout for a penalty of their own turned down for handball in just the second minute when Michael Bostwick's shot struck a defender.
A scrappy first half saw both goalkeepers have to make one good save each, with Rovers' Anssi Jaakkola beating away a drive from Jack Payne and Imps stopper Josh Vickers tipping over a header from Nichols.
City went close early in the second half when Harry Anderson's low cross was inches away from being turned home by Payne.
Rovers broke the deadlock midway through the second half, and it proved to be the match-winning goal.
Eardley got caught the wrong side of Nichols, who fell under the defender's challenge, and the in-form Clarke-Harris sent Vickers the wrong way from the spot.