Shrewsbury took a step rather than a leap towards League One survival but they were left aggrieved by a controversial second-half penalty.
Twice Graham Turner’s men appeared to be heading for their fifth away success this year after, first, Matt Richards had capitalised on a goalkeeping blunder from Mark Gillespie and then Yado Mambo had popped up with his maiden senior goal.
But twice they let a disjointed Carlisle off the hook and their eventual passage, to what could still be an important point, proved to be as uncomfortable as their supporters’ trip had been up the M6.
One coach-load of Town fans was even forced to turn back to Shropshire after severe traffic hold-ups left them stranded in the Preston area.
No doubt, they were left grimacing by their radios at the two penalty awards, which allowed Lee Miller to fire the Cumbrians back on terms twice.
Miller’s first, just a minute after Richards sailed a free-kick from long range past the stricken Gillespie, looked harsh in the extreme with referee Mark Haywood penalising Luke Summerfield for a handball inside the box.
He was swiftly surrounded by Town players, convinced the cross had ricocheted off a Carlisle arm instead.
The second, though, they could have few complaints about as Chris Weale uncharacteristically dashed off his line to upend Jon-Paul McGovern and hand Greg Abbott’s side another lifeline.
But when they reflect on a game in which their defensive resources were eroded still further by the loss of Darren Jones to a dislocated shoulder then this draw, which stretches their unbeaten run away from the Greenhous Meadow to three games, should be viewed as more than creditable.
Boss Turner made two changes to the side on duty in the 1-1 draw at Crewe.
Deadline-day loan signing James Hurst came in at right-back for the injured Cameron Gayle, while Steve McGinn was favoured ahead of Dave McAllister in central midfield.
Birmingham striker Akwasi Asante – also drafted in on loan before Thursday’s deadline – made the bench.
Town offered the early attacking intent with Summerfield and Joe Jacobson attempting speculative efforts from distance, both of which cleared Gillespie’s goal.
Carlisle suffered an early blow when left-wing threat Matty Robson limped off to be replaced by David Symington.
Town pressed up the pitch and Tom Eaves should have made the most of a lofted pass from skipper Matt Richards, but failed to get the ball under control, allowing Sean O’Hanlon to hook the ball clear of the home box.
Yet the imposing Bolton youngster shrugged off that moment of uncertainty with his willingness to hold up the play and shoot on sight.
Twice in the space of a couple of minutes he fired goalwards, with his second effort an attempt to emulate his goal at MK Dons as he cut from the right of the box and drove for the far corner. This time his effort flashed past the post.
But it was Salop’s turn to be hit by injury and what a cruel blow it was with ‘Mr Consistency’ Jones having to be helped off clutching his shoulder in agony after coming off the worst from an aerial collision.
Connor Goldson, who had been unfortunate to be left on the bench after the signing of Hurst, was drafted on to partner Mambo.
But Carlisle made the most of the disruption in the visiting back-line and frontman Miller went close with a volley, which flew just past the upright.
Then Jordan Mustoe’s fierce 25-yard drive forced Weale into a back-stretching push-over. Mustoe raced to the by-line to offer Mark Beck a far-post header, but under pressure the frontman could only land his effort on the roof of the net.
Town eased the pressure as the half closed and Jon Taylor’s inswinging free-kick, on the half-time whistle, left Gillespie taking evasive action to push the ball clear of his near post.
But Carlisle restarted in attacking mode with Weale fielding Beck’s close-range header from a free-kick needlessly conceded by Hurst, who was booked for his lunge on Mustoe.
But the West Brom loanee almost made up for his glitch with a powerful attacking run, which went close to setting up Richards with a far-post finish.
And it was Richards who made the first strike, although he was as bemused as the home support when his routine free-kick from 35 yards beat Gillespie, who misjudged the flight allowing the ball to drop under his bar on 63 minutes.
The lead was short-lived, though, as Summerfield’s alleged handball was punished by Miller.
The striker beat Weale at his right-hand post for the spot-kick equaliser, just 60 seconds after Town had gone ahead.
Mathieu Manset’s arrival posed new problems for the Salop defence.
The former Hereford and Reading striker went close with an angled drive before Mustoe’s audacious 40-yard chip almost caught out Weale.
But it was Mambo who looked to have delivered Town the win they craved, with 14 minutes left, after Gillespie completed a woeful afternoon by spilling Eaves’ near-post shot. Substitute Asante played his part by keeping the ball alive before Mambo prodded in from close range.
Sadly, again Town failed to hold the lead as Weale’s rush of blood left McGovern flying over the keeper’s dive as he surged into the box to finish. Miller did the honours for the second time from 12 yards, picking the same spot in the corner to beat the keeper for Carlisle’s second equaliser.