The opening exchanges were played out in a cagey manner, as Colclough advanced down the left and won a couple of corners in quick succession.
Admiral Muskwe’s fierce early shot was blocked and Jordan Clarke got his body in the way of the rebound.
John McAtee won a corner in the 11thminute as he attacked, and sent a shot towards goal from the edge of the area which was deflected wide.
From the subsequent set-play, Kgosi Ntlhe sent a deflected shot just wide after Andy Butler’s header had put the ball into the danger area.
On the 20-minute mark, George Miller linked up with McAtee and the former fired a low effort across the Leicester goalkeeper, but he got down well to save.
With 22 minutes gone, Colclough drilled an effort from the edge of the area, which Eldin Jakupovic dived to his right to tip away.
Soon after, Colclough had an effort from the edge of the area deflected over the crossbar. Then, from the subsequent set-play, the winger found Ntlhe with his cross, but his back-post header was saved by the goalkeeper.
The visitors attacked with around half an hour gone, but George Hirst sent a speculative shot over the crossbar from the edge of the area following a pass from the right flank.
A further Iron chance arrived on 33 minutes as Clarke’s right-wing cross found the head of Miller, who sent his header just over the crossbar.
Five minutes before the break, Hirst looked to strike a free-kick from 30 yards towards goal but Jacob Bedeau got a good block in and the danger was cleared away.
Just before the break, Abo Eisa cut inside after a corner was only partly cleared, and sent an effort goalwards which was comfortably saved by the away goalkeeper.
Early in the second period, Bedeau came close as he connected with a Colclough corner from the left wing, but he sent the ball over the crossbar.
On 51 minutes, Miller advanced down the right side and tried to send a cross in for Eisa, but it went over his head and the Foxes cleared.
Latching onto a pass from Miller, McAtee came close with 55 minutes gone. He advanced into the area and saw his low shot across goal tipped away superbly by Jakupovic.
McAtee came close again not long after, as he got on the end of a right-wing cross from Colclough, who had received a Levi Sutton backheel. However, he shot wide from close range.
The next player to come close was again McAtee on 60 minutes. Substitute Andy Dales worked hard to win the ball down the left wing and sent a low cross in for the frontman, who fired across goal but wide.
The Foxes threatened in the 64thminute as low powerful cross into the box by Calvin Ughelumba was blocked away by a challenge from Ntlhe.
Subsequently, from one of a number of corners won in quick succession for the Foxes, Bedeau made a great block from a Luke Thomas effort which would have tested Jake Eastwood.
The away side continued to have a good spell of pressure, and the next to come close was Callum Wright, who headed wide under pressure from Andy Butler and Bedeau. Soon after, Nthle got a great block in on an attempt by Ughelumba from close range.
After a corner was won, Dales sent the ball into McAtee but it was just too quick for him and the Foxes cleared. The set-piece came after McAtee slid the ball into the path of Ntlhe and the left-back’s cross was headed behind by Filip Benkovic.
The Foxes counter-attacked with around 10 minutes left, but Wright sent his effort from distance well over the crossbar.
Scunthorpe’s next opportunity came with seven minutes left, as Regan Slater fizzed a shot wide following a lay-off from Dales.
Soon after, Colclough drove forward through the centre and his shot was turned wide for a corner. From the subsequent corner kick, the ball reached the same player, who saw a curled effort deflected over the crossbar.
Leicester’s goal arrived with four minutes left as Kiernan Dewsbury-Hall received the ball on the left side of the area and turned before firing into the back of the net.
But just two minutes later, Scunthorpe were level as Colclough fired in from close range after Ntlhe’s left-wing cross was cleared into his path.
The penalty shoot-out unfolded as detailed below:
IRON – Colclough missed (0-0)
LEICESTER – Dewsbury-Hall scored (0-1)
IRON – Miller missed (0-1)
LEICESTER – Muskwe missed (0-1)
IRON – Dales scored (1-1)
LEICESTER – Eppiah scored (1-2)
IRON – Sutton missed (1-2)
LEICESTER – Thomas scored (1-3)
IRON: Eastwood, Clarke, Ntlhe, Butler, Colclough, Sutton, Slater, Miller, Eisa (Dales, 58), Bedeau, McAtee (Butroid, 80).
IRON SUBS NOT USED: Collins, Potts, O’Malley, Pugh, Hornshaw.
LEICESTER U21s: Jakupovic, Benkovic, Muskwe, Leshabela, Johnson, Hirst (Eppiah, 75), Wright (Shade, 83), Ughelumba, Dewsbury-Hall, Clark, Regba (Thomas, 57).
LEICESTER U21s SUBS NOT USED: Stolarczyk, Daley-Campbell, Tee, Gyamfi.
ATTENDANCE: 572.
