Two first-half goals were enough to give Exeter a crucial victory against promotion-chasing Lincoln.
Exeter started brightly and Carl Pettefer thumped a shot past the post in the opening minutes.
Defender Santos Gaia then shot narrowly wide after getting on the end of Pettefer's corner.
Lincoln seemed happy to sit back and soak up the early pressure and offered little in the opening stages.
Exeter took the lead in the 21st minute. Pettefer's corner was met by Chris Todd whose header was parried by goalkeeper Alan Marriott and James Coppinger was on hand to blast it home from close range.
Exeter should have stretched the lead five minutes later. Gareth Sheldon's fine pass found Sean Devine on the edge of the box and the striker thumped a powerful shot just past the post.
Richard Butcher had Lincoln's first shot on goal from the edge of the box after half an hour but the effort was comfortably saved by Kevin Miller.
Seven minutes before half time Sheldon made it two. The makeshift striker was found by Gaia's long pass and sprinted into the box before striking a low shot into the bottom corner.
Lincoln attempted to chase the games after the break and Mark Bailey forced Miller to save well with a free kick from the edge of the box.
But the visitors never really looked like a side chasing promotion.
Ben Futcher curled a shot over the bar in the closing stages but the visitors rarely looked like scoring.
In the closing stages Devine came close to stretching the scoring when he curled a shot wide from 15 yards.
Exeter boss Gary Peters said: "I am delighted with the players. We had to battle for everything and they were superb. I am not looking at the tables yet, there is still a long way to go." Lincoln boss Keith Alexander said: "We were out-fought and out-battled by a team fighting for its life and that was very disappointing."