The Imps could not find a way past Ipswich Town as they suffered a narrow defeat at the LNER Stadium.
The Imps started brightly with an early Tom Hopper pass looking for Anthony Scully deflected away from its intended target.
The first corner for the home side came after 12 minutes, with Hayden Coulson blocking the ball wide and Chris Maguire threatening after 16 minutes.
A smart move saw the ball sprayed out to Cohen Bramall on the left wing, and his square ball found the Imps’ No.10 whose low shot was blocked behind by Cameron Burgess.
A searing Scully run into the area was halted by George Edmundson, with the referee Ben Speedie waving away appeals for a corner.
The Tractor Boys weathered the early pressure and threatened for the first time as the match reached the half-hour point, with Burgess crashing an header off the bar a minute before they took the lead with their second real chance of the game.
A deep cross from Hayden Coulson was met by Macauley Bonne, who looped a header past Josh Griffiths.
The Imps pushed for a leveller as the break approached, with Lewis Fiorini flashing a low effort agonisingly close of the near post after collecting the ball from Scully on the left in the closing stages of the half.
There were no changes from either side at the interval, with the Imps again starting the second period brightly as they looked to get back on level terms.
They had the ball in the back of the net in just the third minute of the half, with a lovely Fiorini cross finding Regan Poole - the right-back fired home but the assistant’s flag was up to curtail celebrations.
A vital header from Janoi Donation denied Scully a glorious opportunity as Hakeeb Adelakun dinked a lovely ball over the visitingg defence.
Lewis Montsma went close with an effort from distance, while Bramall also saw an effort blocked behind by Wes Burns. Fiorini also forced a save out of Vaclav Hladky on the after collecting a short free-kick.
Griffiths was not forced into action until the 77th minute, when he stood up well to palm away Scott Fraser’s shot.
Adelakun fired a powerful effort which was straight at Hladky, but ultimately with the visitors defending deep and in numbers there was no way back for the Imps.