United had gone in front midway through the first half courtesy of a Sam Winnall header, but were forced back by their hosts for the final stages of the second period as the Shrimps dug deep in pursuit of a valuable equaliser.
That goal was to eventually come deep into injury-time when Sampson rose highest to head home a cross from close-range to salvage a valuable point for the struggling Lancashire outfit as they continue their fight to avoid relegation.
In truth, the Iron had goalkeeper Sam Slocombe to thank for a string of fine saves – while they were also aided by a controversially disallowed goal from the hosts during the second half.
Despite being held to a solitary point against the Shrimps in Lancashire, United moved two points clear at the top courtesy of Rochdale falling to a 3-0 home defeat against Southend.
They also hold a five-point lead over chasing Fleetwood Town as they look to secure promotion with just three games of the regular campaign now remaining.
United manager Russ Wilcox kept faith with the same side which started last weekend’s 2-2 draw against Bury at Glanford Park, with the game against the Shrimps coming too soon for the injured Sean McAllister.
Meanwhile, Morecambe manager Jim Bentley also named an unchanged XI from the Lancashire outfit’s 2-2 draw at Fleetwood six days ago as they began the afternoon in a 3-4-3 formation looking to end a run of seven games without a win.
The home side began in positive fashion, but soon found themselves pushed back into their own half when Hakeeb Adelakun manoeuvred the space to swing in a cross from the left in the fifth minute. Adelakun’s centre picked out Winnall on the run, but the Iron’s leading marksman thundered his header over from six yards.
Three minutes later, the Shrimps created their first meaningful opportunity when tidy interplay from a throw-in saw the ball arrive at the feet of Padraig Amond. The Morecambe forward showed excellent technique to flick the ball over his marker and into the box, only to then lack composure as he blazed a left-footed half-volley well wide.
With 11 minutes gone, United found themselves tested once more when an initially innocuous looking ball from midfield bounced in the Shrimps favour and caused confusion for the Iron back-line. The industrious
Kevin Ellison looked set to take advantage and reach the ball ahead of Slocombe, but Eddie Nolan read play expertly to nip in just in time to avert the danger.
Such defensive awareness was then matched by David Mirfin with the match approaching the 15-minute mark as he stole in at the last to clear behind his own goal when Shrimps attacker Jamie Devitt appeared favourite to reach the ball first. The Iron defended the subsequent corner manfully, and three minutes later had a flag-kick of their own following good work by Terry Hawkridge.
Hawkridge himself swung across the set-piece straight onto the head of Mirfin, who was only denied by an excellent tip over from Morecambe goalkeeper Barry Roche at the expense of another corner. The hosts dealt with the second delivery more efficiently; Roche punching clear before gratefully claiming Nolan’s cross from deep after the United defender had picked up the loose ball.
The Iron had grown into the game gradually, and midway through the half took the lead courtesy of Winnall’s 23rd goal of the season. Breaking at pace down the right following a stalled Morecambe attack, Hawkridge found a yard on his marker to swing an inch-perfect cross into the path of his team-mate; Winnall’s downward header bouncing into the turf before looping beyond the grasp of Roche to put United in front.
Not content to rest on their laurels, the away side immediately poured forward in search of a second, and on 25 minutes Marcus Williams won a corner when his left-sided cross was blocked behind. The set-piece was met firmly by Dave Syers attacking the ball from deep, but the former Doncaster midfielder’s effort was scrambled off the line despite claims to the contrary from a number of United players.
The hosts looked to respond, and just after the half-hour mark a teasing cross from Devitt seemed to be headed for the onrushing Ellison at the far-post with Slocombe back-pedalling. Once again though, it was Nolan who read the danger as he crept ahead of his man to head away; Shrimps winger Devitt going in the book barely a minute later for a late tackle on Hawkridge on halfway.
After a relative lull in goalmouth action, the Iron came forward once more with four minutes of the half remaining when Mirfin collected the ball deep before carrying well into Morecambe territory. The central defender spread the ball wide into the path of the overlapping Sparrow, only for the 32-year-old’s cross to be out in the final meaningful attack of the half.
As had been the case in the first half, the home side began with purpose after the restart as they attempted to navigate a way back into the contest. With 49 minutes on the clock they appeared to have found such the beginnings of such a route, but were to be denied when Niall Canavan raced in to take the ball off the toes of Amond as he raced towards the United penalty-area.
Instead it was the Iron who came close to doubling their lead just two minutes later when an intelligent pass from Syers put Winnall through on goal. The United striker tried to take it around Shrimps goalkeeper Roche, only to find his path to goal blocked by the sprawled legs of the ‘stopper in front of over 1,000 boisterous visiting fans.
Despite having the better of the early exchanges in the second half, the Iron had to remain resilient at the back in order to keep the hosts at bay as they searched for an equaliser. A warning of the containing danger Morecambe presented came on 58 minutes, when Slocombe was forced to stoop low to gather a fierce Andrew Wright drive from distance.
Further threat was to come as the game edged past the hour-mark when trickery from Devitt created space down the left. The winger moved inside before firing a low ball across the face, with none of his colleagues on hand to attack the ball in a crowded penalty-area when the faintest of touches would surely have levelled proceedings.
Buoyed by that the home side pushed forward with renewed energy, and on 61 minutes forced a corner when a devilish cross from the right was headed over by Nolan with Slocombe having come for the ball.
Although the initial delivery from the set-piece was cleared, the Shrimps refused to be pressed back and only saw an end to their spell of dominance come to an end when a loose pass sailed out for a goal-kick.
A challenging period for the Iron prompted Wilcox to make his first change of the afternoon on 65 minutes, as he replaced Adelakun with the more experienced Paul Hayes. The alteration came within inches of having an immediate effect, with Hayes losing his man from a Hawkridge corner to volley at goal – only to see his strike blocked a yard before it reached its intended target.
With Morecambe trying to get back into the game, the match was becoming increasingly stretched, and two minutes later Devitt again caused problems when he moved down the left before pulling back across goal. First to react to the danger was Mirfin, who did just enough to cut out the cross despite slipping, prior to showing the instinct required to recover and clear his lines.
Shrimps boss Bentley then opted to make his first substitutions of the contest, bringing on Ryan Williams and Jack Redshaw in favour of Amond and Andy Parrish with just under 20 minutes remaining. Williams was instantly involved in proceedings, skipping down the left before firing at Slocombe who fell on the ball at the second attempt having spilled the pacey winger’s initial effort.
Five minutes later, the Shrimps had the ball in the net when lashed home from 20 yards off the underside of the bar, but referee Steve Rushton had already come to United’s rescue by awarding a free-kick for handball on the edge of the area just seconds earlier. Williams did his best to right what he and his side perceived as an injustice, but Slocombe acrobatically tipped his superb free-kick wide at full-stretch.
The home side then made their final allowed change with eight minutes remaining when Sampson entered the fray in place of Wright as they began to look ever more likely to take something from the game.
Referee Rushton was not endearing himself to the hosts, and two minutes later did little to help his cause in Lancashire when he waved away a penalty appeal after Sampson tumbled just inside the box. Despite that, Morecambe continued to press and with two minutes left Nolan was forced to head behind from under his own crossbar as the Shrimps threw everything at rescuing a point from the game.
That offensive intent was fully understood by Wilcox, who reacted by offering a cameo to defender Luke Waterfall in place of Sparrow for the final moments. Although the intention of Waterfall’s introduction was to tighten matters at the back, there was little he or anyone else could do when a corner was attacked on the volley at the back-post by Devitt – Slocombe producing a stunning save to palm the ball behind.
As the fourth official indicated six minutes of additional time, Slocombe was again the hero when he flung himself across the goalmouth to tip a rasping drive from Shaun Beesley around the post as he formed an increasingly one-man barrier against the Lancashire outfit.
They would spend the remaining minutes throwing everything at the visitors, and earned a deserved last-gasp point their efforts deserved when Williams jinked his way past Madden before lofting to the back-post towards Sampson. The Shrimps substitute rose high to meet the ball, heading low into the net to salvage a late draw for his side.
The result leaves United two points clear of Rochdale at the top of the division, while they also sit five points ahead of chasing Fleetwood Town as they look to secure an return to League One at the first time of asking.
They will not have long to wait to continue that bid, with the Iron’s next match seeing Oxford United travel to Glanford Park on Easter Monday.
Morecambe: Beeley; Hughes (capt.), Parrish (Redshaw, 70), Edwards; Mustoe, Beeley; Kenyon, Wright (Sampson, 83); Ellison, Amond (R. Williams, 70), Devitt.
Substitutes not used: Arestidou, Threlfall, Diagne, Marshall.
Scunthorpe United: Slocombe (capt.); M. Williams, Mirfin, Canavan, Nolan; Adelakun (Hayes, 65), Sparrow (Waterfall, 89), Syers, Hawkridge; Madden, Winnall (Burton, 90).
Substitutes not used: Severn, Ribeiro, Godden, Collins.
Referee: Steve Rushton (Staffordshire).
Attendance: 2,952 (1,194 away).