The Imps were unable to claim a point as they fell to a narrow defeat at early Sky Bet League One pacesetters Wycombe Wanderers.
The home side went ahead after just three minutes when Jordan Obita’s deep cross was headed in at the far post by Sam Vokes and, despite going close through Anthony Scully and Ted Bishop, the Imps suffered their second league loss of the campaign.
The visitors nearly got a quick leveller after a smart counter-attack. Hakeeb Adelakun held the ball up well and laid it off to Scully, whose low shot was stopped by David Stockdale. Chairboys defender Anthony Stewart had to be alert to bundle Tom Hopper out of the way as he closed on the follow-up.
Regan Poole saw an effort blocked before a break in play when Hopper was left with a nasty cut to a cheek after again challenging with Stewart in the air.
Defender Adam Jackson had to be alert to get in a great block on Daryl Horgan’s shot, then moments later he threatened at the other end of the pitch.
The centre-back got on the end of Liam Bridcutt’s delivery after a well-worked set-piece from the Imps, but Stockdale was able to hold his header at the second attempt.
That was the closest the visitors went to levelling before the break, but Conor McGrandles curled a smart effort wide from outside the area and Scully flashed a header just wide from Poole’s cross.
Dan Nlundulu was sent on at the break, replacing Hopper, and he was in the thick of it from the off.
A Scully cross from the left whizzed just ahead of him, with the on-loan Southampton man in a great position but just unable to turn it home.
The home side threatened themselves early in the second period, with Nick Freeman firing over from distance and Jack Grimmer hammering a header over from a corner.
They also caused some consternation in the Imps’ area through a deep free-kick from Jacobson, with Stewart and Obita both looking to get on the ball.
The game became end-to-end as it went into the final stages, with Jacobson making a great tackle on Scully to halt an Imps attack before Jackson was called upon at the other end of the pitch to block a Garath McCleary effort.
Ted Bishop and Lewis Fiorini, replacing McGrandles then Sorensen, were sent on as Michael Appleton sought a leveller.
The two substitutes combined in style after 78 minutes, with Fiorini’s cross from the left providing Bishop with an opportunity at the near post - with Stockdale grateful the midfielder’s volleyed effort was straight at his chest. Fiorini also sent an effort over from distance.
Scully found himself through on goal after Fiorini’s effort was deflected. Stockdale scrambled well to turn his shot away but the offside flag was up anyway.
And the Irish forward won himself a free-kick on the edge of the area after 90 minutes. He attempted to lob the ball into the far top corner but his effort went over.