Carlisle failed to score for the fifth successive game as they were held to a 0-0 draw by promotion rivals Luton.
The injury-hit Cumbrians had to show some dogged defensive work to keep out the Hatters' 22-goal leading scorer Danny Hylton who was responsible for side's best effort in the second half - a shot turned onto the crossbar.
There were some feisty early exchanges and referee Lee Mason was kept busy, booking Luton's Hylton and Olly Lee and Luke Joyce of Carlisle, all inside the first 20 minutes.
Hylton displayed his intentions when he fired a low shot across the face of the Carlisle goal after a determined break by Pelly Ruddock.
However, Carlisle came close to opening the scoring in the 27th minute when Luton's defence failed to deal with a long throw from the right and Jamie Proctor's shot from inside the six-yard area was blocked on the line by the combined efforts of goalkeeper Matt Macey and Alan Sheehan.
Sheehan, skippering Luton on his 50th appearance for the club, was involved defensively again before the break, getting a foot to John O'Sullivan's 20-yard drive, causing the ball to loop up onto the top of the net.
Carlisle came under severe pressure after the break and it took a fingertip save from Mark Gillespie to prevent Hylton giving Luton the lead in the 65th minute. The striker's powerful right-foot shot was heading for the top corner until the goalkeeper, at full-stretch, deflected it onto the crossbar and over for a corner.
There was a lengthy hold-up for an injury to Hatters defender Dan Potts who was hurt in a clash of heads in his own six-yard box and was eventually stretchered off. The break led to 10 minutes of added time during which neither side could grab a winner.