The Football League debut which franked all the recent Portsmouth soundbites
The youngster jumped up and down to keep warm on the sidelines at a crisp Sincil Bank, awaiting his signal to finally be introduced.
Eventually, on 89 minutes, it was his time to enter the fray. Off came Marcus Harness, with Mnoga taking up an unfamiliar right-wing role.
Kenny Jackett's not the sort of manager to make substitutes through sentiment.
Even despite Mnoga travelling up and down the country for the majority of the season – as either 19th man or an unused substitute – the boss wouldn't have handed him a maiden League One bow if it didn't make sense tactically for Pompey to retain their 3-1 lead.
All the recent soundbites coming out of the Fratton camp is that Mnoga's ready for the third tier. From Jackett to Joe Gallen to team-mates such as Ellis Harrison, they’re all convinced of his qualities.
It's why Pompey have been reluctant to send him out on loan to garner regular first-team experience in the National League. It's why he's ahead of senior pros Paul Downing and James Bolton in the pecking order.
And, although his cameo at Lincoln was fleeting, the early evidence suggests that is the case.
Mnoga’s performances in the EFL Trophy have been eye-catching, especially in last month’s win at Southend.
The third tier was also going to be a substantial step up, though, given the League Two basement side fielded a weak side that night.
Yet it took Mnoga a matter of seconds to make his mark in League One.
Lincoln's Theo Archibald tried to sally down the left – but his attempt was futile.
There was simply no passing Mnoga. With the utmost strength and ease, he bullied the Imps man off the ball to win possession for the Blues.
Then, in stoppage-time, the defender's eyes lit up when he was set free on goal by Ryan Williams, but he couldn't quite engineer a path into the box to get a shot off.
During every involvement in his five minutes on the pitch, waves of encouragement from the bench were bellowed at Mnoga from his team-mates.
That's always a sign he's clearly well-rated and respected despite being in the infancy of his senior career.
It was a proud moment for Mnoga, no doubt, and further proof of his hurtling development he's made from pre-season onwards.
Callum Johnson's eye-catching start since his arrival from Accrington means the England under-19 international will have to continue to wait a little longer for a full Football League debut.
Jackett's mantra to all of his players on the sideline is to remain ready as injuries can bite at any time. Lee Brown pulling out of the warm-up at Lincoln is a case in point.
And if Johnson were to suffer a similar setback, any previous doubts Mnoga might not be ready to start in the league surely are no more.