The Celtic attacker was visibly stunned by his team-mate’s winner in a youth game against the old enemy on Tuesday.
Robbie Deas was a hero for Celtic’s reserve side on Tuesday night.
The 19-year-old defender scored a last-minute stunner against Rangers as Celtic won the City of Glasgow Cup with a dramatic 3-2 win.
Goals from Jack Aitchison and Mikey Johnston had the Hoops comfortably ahead by half-time, but two quickfire strikes from Gers star Glenn Middleton saw the visitors draw level with five minutes remaining.
Asked on Celtic’s YouTube channel what Johnston was thinking when he saw the centre-back take aim, he said: “‘What is he doing up there?!’
“As soon as he scored I was like ‘Oh my god that’s an absolute screamer’. It was a great goal.”
The victory represented an element of revenge for the Bhoys, who were beaten in the league by Graeme Murty’s side last week.
Deas added: “Getting beaten by them in the league, it just shows what we’re capable of.”
It could be a double celebration for the club if the senior side win on Saturday.
Celtic visit Aberdeen this weekend and victory would confirm their eighth successive Premiership title, regardless of what Rangers do at home to Hibernian on the Sunday.
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