Substitute Max Clayton secured a point for Bolton Wanderers after coming off the bench to net a last gasp equaliser at the Ricoh Arena.
Coventry had taken a first half lead through Marcus Tudgay before substitute Zach Clough earned parity from the spot.
Debutant Stuart Beavon then put the hosts back in front moments later before Clayton, returning after a long injury layoff, had the last laugh with his first goal of the campaign to earn a precious point for the visitors.
Phil Parkinson made three changes from the side that saw off Scunthorpe United 48 hours earlier.
Zach Clough dropped to the bench with James Henry, fresh from his last minute heroics in that victory, starting in his place.
Liam Trotter also returned at the expense of Tom Thorpe, while Derik came in for the injured Lawrie Wilson at right back.
The hosts had the majority of possession during the opening stages and won an early corner which was eventually scrambled away by the Wanderers defence.
Wanderers’ first chance came from a free-kick when Madine was upended. Henry’s resulting right-footed effort from 20 yards though went high and wide without troubling Lee Burge.
Large swathes of the opening half were scrappy as both sides struggled to a grip on the game.
A moment of class from Derik almost gave the visitors the lead when his right-footed half volley following a lay off from Trotter sent Burge diving to his right.
Moments later, the Sky Blues had a gilt-edged chance to break the deadlock when Bevan lost his marker with a superb turn only to steer his shot wide.
The hosts didn’t have to wait long and captain Tudgay nodded into an unguarded goal after Derik and Alnwick didn’t pick up a cross to the far post.
It was a forgettable first-half as far as Wanderers and their 1,751 strong supporters were concerned.
Phil Parkinson opted not to make any changes during half-time and moments after the restart Trotter saw a volley go wide after pouncing onto a loose ball.
The Wanderers manager made a double substitution just before the hour mark with Zach Clough and Max Clayton coming on for Liam Trotter and James Henry.
The positive change had an immediate impact and Wanderers started to get more possession in the Coventry area.
Wanderers got back into the contest on 66 minutes when substitute Clough coolly slotted home from the spot after Madine was fouled in the box by Ryan Haynes who was shown a yellow card for the challenge.
But the parity didn’t last long and Stuart Beavon fired a curling effort past Alnwick just moments later.
Clough was Wanderers’ biggest threat and a good move culminated in his drilling the ball low and wide of Burge’s right hand post.
With ten minutes remaining, Parkinson through on Jamie Proctor in place of Derik with Wanderers playing three at the back. It was a bold but positive move by the Wanderers gaffer.
Coventry had the ball in the back of the net once again but this time the linesman had his flag up for an offside.
But for the second game on the trot late drama saved the day for Wanderers when Clayton drilled home in injury time to send the visiting fans into a frenzy.
Clough was instrumental in the build up with Taylor firing into the box for the young sub to blast home.
Wanderers should have won the game deep into injury but Madine flashed wide after brilliantly controlling in the box.