Winnall produced an expert finish on the stroke of half-time to give his side the lead, and doubled both his and United’s tally just before the hour-mark to put his side firmly in control.
Things could have been made more difficult for the Iron within a minute of Winnall’s second, when a penalty was awarded against David Mirfin, but Sam Slocombe produced an increasingly characteristic moment of brilliance to deny Matt Richards from the spot.
United’s third consecutive win sees them stay within two points of league leaders Rochdale, while also keeping a seven point gap between themselves and the teams outside of the automatic promotion positions.
It also sees them equal a 125-year Football League record of the longest unbeaten run by a manager from the start of their reign, after United’s undefeated sequence under Russ Wilcox was stretched to 23 games on his 50th birthday.
That run now matches the one set in the 1888/1889 season by Preston North End’s William Suddel, who successfully navigated his side through the first 23 matches of the inaugural Football League campaign without losing as the Lilywhites lifted the maiden First Division Championship.
Iron manager Wilcox kept faith with the same starting line-up for the third match in succession, as he looked to build upon the momentum gained by back-to-back wins against Plymouth Argyle and Burton Albion in the previous 10 days.
Meanwhile, Cheltenham boss Mark Yates was forced into a solitary change from the side who fell to a last-gasp 4-3 defeat against AFC Wimbledon on Saturday. That alteration came in the form of right-back Michael Ihiekwe missing out through illness and Mitch Brundle stepping in to replace him, with the Robins retaining their diamond formation deployed at the weekend.
The home side began the brightest, and threatened to break the deadlock in the third minute when Richards broke down the left before crossing towards Jermaine McGlashan. Although the forward managed to get ahead of his marker, he could only head low into the turf, allowing Slomcombe to gather under pressure from Byron Harrison.
United responded, and two minutes later were on the attack themselves; a sharply taken throw-in from Eddie Nolan reaching Gary McSheffrey 35 yards from the goal, with the winger hitting a speculative effort wide of Robins goalkeeper Scott Brown’s left-hand post.
It would be McSheffrey involved again on six minutes, this time earning a corner after his delivery from a free-kick was put behind by the home defence. McSheffrey himself would take the resultant flag-kick, but saw his attempted centre cleared comfortably by the hosts.
Four minutes later, United went close to going in front as Dave Syers showed excellent technique to control a clearance before volleying towards the goal. The strike looked set to test Brown, but eventually skidded narrowly wide of the post, much to the 26-year-old’s frustration.
The visitors continued to press, and Paddy Madden was next to cause problems when he lashed an effort from 25-yards towards the Cheltenham goal. Much like Syers’ attempt barely a minute early, the Irishman had goalkeeper Brown beaten, but was denied by a fraction of an inch as it flew just wide.
The Iron had enjoyed the better of the early exchanges in Gloucestershire, with Sean McAllister managing to dictate the tempo with a series of passes to the flanks. One of those passes wide released Madden down the right on 19 minutes, but his deep centre eluded Winnall, with the Robins regrouping to clear as Syers lurked with intent – eventually earning a free-kick which brought a booking for McAllister.
United remained on the front foot however, and midway through the opening period a measured pass lofted over the Robins defence by McSheffrey looked to have set Madden through on goal. The Dublin-born Madden raced onto the ball, only for goalkeeper Brown to read the play expertly and gather at the feet of the advancing striker.
Having spent much of the half on the retreat, the Robins then launched an attack of their own as the game moved towards the half-hour mark. Midfielder Sam Deering intercepted wide on the right, before displaying the pace required to get past Marcus Williams. However, the Iron favourite used his experience to recover the ground as Deering looked to move into the area, forcing a mistake which saw United regain possession.
That appeared to boost the Robins confidence, and they came forward again on 32 minutes later courtesy of a free-kick from halfway. The lofted delivery was met by club-captain Steve Elliott in the box, but the veteran’s header lacked the power to seriously test Slocombe who claimed with ease.
Slocombe had to be more alert four minutes later, when he was called into serious action for the first time as a sliced clearance from Williams inadvertently found Richards. The 29-year-old Richards nodded towards goal, with Slocombe producing a fine sprawling stop low to his right to tip past the post.
Four minutes before the interval, intelligent play from Mirfin guided United through a dangerous looking moment after McGlashan found space down the Iron left. His cut-back across the face of goal looked set to be converted by Harrison, but the centre-back calmly rolled his opponent off the ball to avert the danger.
The Iron then threatened with a pair of McSheffrey free-kicks; the first of which was narrowly missed by the advanced Mirfin. They were to fare better from the second on the stroke of half-time however, with the Robins failing to deal with a whipped delivery sufficiently, and Winnall improvising an overhead-kick to finish from six yards as the ball bounced around the penalty-area to register his 20th strike of the campaign.
Within moments of Winnall putting his side in front, referee Charles Breakspear brought an end to the half – meaning United went into the break with a largely deserved lead having posed a greater threat than their opponents during the opening 45 minutes.
United began the second period in confident fashion, maintaining possession in the minutes immediately following the restart while also pressing their opponents high up the pitch. Such composure on the ball allowed the Iron to build down the Robins right in the 51st minute, with neat interplay between McSheffrey, Winnall, and Syers breaking down as the visitors reached the final-third.
The visitors needed to improve if they were to get back into the game, and in the 55th minute won a corner after a retreating Winnall cleared behind. That didn’t signal the end of the Robins attacking purpose though, with Madden fulfilling his duties admirably next by tracking back to block a cross from the left before McSheffrey was cautioned for a foul out wide.
The attacking duo of Winnall and Madden had shown their commitment to the cause, and the former got just reward for his selfless attitude just four minutes later when he notched his second of the evening to double United’s advantage. Once again, the goal came from a McSheffrey free-kick; the devilish in-swinger being flicked into the net by the leaping Winnall to offer the Iron some breathing space.
That comfort looked set to be severely tested with a minute of the game re-starting, when Mirfin was adjudged to have pushed McGlashan in the area after the striker edged past the United defence – with referee Breakspear pointing to the spot. However, Slocombe produced yet another trade-mark penalty save to deny Richards from 12 yards, diving low to his right to palm away and preserve the Iron’s two-goal lead.
The missed opportunity from the Robins to pull a goal back prompted manager Yates to make a double substitution on 65 minutes, as David Noble and Jason Taylor were replaced by Ashley Vincent and Jamie Cureton.
Despite those changes, the penalty miss looked to have left the hosts deflated initially, and instead it was the away side who looked more likely to further extend their lead as the match moved into the final 20 minutes. In response, Yates made his final switch on 71 minutes, this time introducing Terry Gornell in favour of Harrison as he sought a formula most likely to provide the catalyst for a Robins fight-back.
One home substitute who appeared capable of providing the spark to reignite the Robins was the veteran Cureton, and nimble work from the front-man on 73 minutes drew a foul from Niall Canavan which saw the United defender booked. Fellow replacement Vincent stood over the ball at the free-kick, but his powerful drive was directed straight into Slocombe’s midriff.
Another free-kick caused relative concern for the Iron back-line two minutes later, when a looped delivery from halfway eventually fell the way of Troy Brown. The defender attempted a curling effort from just inside the area, but missed the target as it whipped over the bar with Slocombe shaping to dive.
With 10 minutes remaining, Wilcox made a double alteration as he withdrew Winnall and McSheffrey for Paul Hayes and Hakeeb Adelakun respectively. Hayes was immediately in the thick of the action, delicately sliding a precise pass into the path of Terry Hawkridge, who jinked past his man before being tackled; the ball falling to Madden whose drive from the penalty-spot was beaten away by Brown in the Robins goal.
The visitors were becoming increasingly desperate in their efforts as the minutes ticked down, but an excellent take-down from Vincent 18 yards from goal on 82 minutes suggested the beginning of an opportunity.
However, the substitute’s finish didn’t match his own personal build-up, with the 28-year-old’s volley flashing well over from inside the area.
A sign of the Robins eagerness to navigate a way back into the game was the repositioning of Elliott as a make-shift striker for the closing stages, and the tactical change almost forced an chance three minutes later when the ball fell to Richards in the area. The former Ipswich academy product looked to atone for his earlier penalty miss, but failed to do so as he fired over from close-range.
As the clock ticked towards five minutes of additional time, Wilcox made his final substitution of the night as he offered a brief cameo to Matt Sparrow in place of the cautioned McAllister. The remaining moments were seen out with little concern by United, ensuring they completed a crucial victory as they continue their push for promotion from League Two.
The result sees the Iron retain their seven point lead over fourth-placed Fleetwood Town, with just seven games of the regular campaign now remaining as Wilcox’s team look to complete a memorable return to League One at the first time of asking following relegation last season.
United will not have long to wait as they seek to continue that bid, with strugglers Wycombe Wanderers next up for the Iron when they visit Glanford Park on Saturday.
Cheltenham Town: S. Brown; Jombati, Elliott (capt.), T. Brown, Brundle; Noble (Vincent, 65); Richards, Taylor (Cureton, 65); Deering; McGlashan, Harrison (Gornell, 71).
Substitutes not used: Roberts, Braham-Barrett, Kotwica, H. Williams.
Scunthorpe United: Slocombe (capt.), M. Williams, Mirfin, Canavan, Nolan; McSheffrey (Adelakun, 80), McAllister (Sparrow, 89), Syers, Hawkridge; Madden, Winnall (Hayes, 79).
Substitutes not used: Severn, Ribeiro, Waterfall, Alabi.
Referee: Charles Breakspear (Surrey).
Attendance: 2,080 (237 away).