John Robertson has watched Leigh Griffiths grow from a precocious 16-year-old who caught the eye in a half-time warm-up to a Scotland striker being tipped to be a Celtic goalscoring great.
Robertson was no slouch in the scoring front himself, setting a record of 214 league goals for Hearts and earning 16 international caps as a result.
Still only 25, Griffiths has found the net 116 times on league duty for his five clubs and has represented his country six times.
It was a potential that Robertson spotted before signing his fellow striker for Livingston from Leith Athletic in 2006.
"Sometimes you have a hunch," said the former Inverness Caledonian Thistle, Hearts and Ross County manager.
"It was actually half-time in a reserve game. He was rattling these shots in from everywhere and I had asked Graeme Robertson, who was a coach at the time, and he said he was a trialist. I said throw him on and see what he's like.
"He scored two goals - and they were wonder goals - and you are thinking 'wow'.
"The board decided at the time that, although the budget was already spent for the youth team - it was January, Pearse Flynn found the money to give Leigh the chance to sign for us.
"He was in the first team by the end of that season."
'Goals from all angles'
Griffiths scored 24 goals in his two-and-a-half years with Livi and went seven better in his 18-month spell at Dundee.
A move to Wolves followed in early 2011, but he returned to Scotland with two seasons on loan at Hibernian.
His scoring form at Hibs caught the eye of then Celtic manager Neil Lennon and, after briefly returning to Wolves, Griffiths moved to Glasgow midway through season 2014-15.
Griffiths's goals contributed to Celtic's third successive top-flight title win under Lennon, who soon moved on to be replaced by Ronny Deila.
The Norwegian initially left the striker out of his starting line-up, but by the dawn of 2015, Griffiths was becoming a regular again and has carried his scoring prowess from last season into the current campaign.
He netted his 14th goal of the season to put Celtic in front against Hearts in Wednesday's Scottish League Cup quarter-final and then set up what proved to be the winner by Tom Rogic in the 2-1 win.
"He did very well as a young lad," explained Robertson. "He's a terrific talent. Very raw but can score goals from all angles and, unfortunately from a Hearts perspective, he showed that last night.
"And that was the difference. It was a very tight game, with not much between the teams and then Leigh produced two pieces of magic.
"The goal itself was just stunning. He really is at the top of his game, he's enjoying his football and that showed.
"He waited patiently and, when his chance came, he turned it into a wonderful goal. Two very even sides last night and it was his magic that separated them.
"Talent is nothing without hard work and he's worked hard at the various clubs he's been to. He looks like he's settled now and it looks like he's enjoying his football.
"No matter who he plays for, he scores goals.
"The international scene will be another target for him. He's been drifting in and out of the squad. I'm sure [Scotland coach] Gordon Strachan will be thinking it is a chance to give him an opportunity."
New competition for striking place
With Carlton Cole joining Celtic as a free agent earlier this month, Deila has three obvious front men to lead his attack, having signed Nadir Ciftci from Dundee United in the summer.
"Maybe Ronny wants to freshen things up," speculated Robertson. "If you look at the three strikers, they are completely different.
"Carlton Cole is more your mainline striker, target man. Nadir Ciftci is a bit of both - he can hold the ball up well, he can act as a target man and he can bring people into play and Leigh is your out-and-out goalscorer as well as his link-up play."
Another who has watched Griffiths's career with interest is his former agent, Darren Jackson, the former Hibernian and Scotland forward who was until recently first-team coach at Dundee United.
And the 49-year-old believes "there's no doubt he can get better".
"From day one, you already knew he was going to be a goalscorer," said Jackson.
"He just takes one touch and doesn't let the goalie set and he's got a wonderful strike on him.
"He has 100% belief in himself that he'll score goals every time he goes on that pitch. It is just wonderful to watch him."