Armstrong Oko-Flex was linked up to boss Neil Lennon via his AirPods on the Celtic bench.
The teenage debutant went viral on social media after being pictured wearing the earphones up until seconds before he stepped onto the pitch.
He enjoyed a late cameo during the depleted Parkhead side's 1-1 Premiership draw with Hibs.
And now coach Gavin Strachan, in charge of the team for the evening, has revealed Lennon was on the other end offering some final words of wisdom.
Strachan told Sky Sports: "Yes (it was the manager speaking to him).
"He was just getting some messages to him before he came on the pitch.
"Everyone uses every bit of technology available to them. We used it, it's good for a young player to hear the manager's voice before he goes on the pitch."
Celtic were without 13 first team players as they dropped yet more points in the race to hunt down leaders Rangers.
Christopher Jullien's positive Covid-19 test ruled out a large chunk of the champions' squad and they not sit 21 points behind Steven Gerrard's team.
David Turnbull 's inch-perfect free-kick looked set to have snatched the points for the hosts before Kevin Nisbet stabbed home a stoppage time equaliser.
Celtic will be similarly short on top stars Saturday's clash with Livingston before facing the Lions again just few days later on Wednesday, January 20.
It's unclear from which date the isolating stars have been told to complete their 10 days quarantine and Strachan admits he doesn't know if any will be able to return for a visit to the Tony Macaroni Arena.
He said: "I'll be honest, I'm not that privy to it. It's been that much of a whirlwind in the past 24 hours, I'm not entirely sure."
