Greg Kiltie might not have played alongside Greg Taylor too often at Kilmarnock. But having known the Celtic full-back since before the pair were even into double digits, there were never any doubts over his quality.
The St Mirren midfielder, 26, had first met Taylor at around nine years old when the pair were in the Rangers academy.
On Sunday, Kiltie will go up against his former Kilmarnock team-mate as St Mirren plot another shock win over the otherwise unbeaten league leaders this term.
“He’s been excellent, probably one of Celtic’s most consistent performers," said Kiltie of pal Taylor. "Especially before the injury he got against Rangers. He’s been tremendous.
"I think he’s shown everybody that he’s gone from stride to stride. He’s got better and better so I think he definitely has proven himself.
“The way Celtic plays suits him. He’s very good technically so he fits into their system. The way they want to play is perfect for him as a left-back."
Taylor had played as a central midfielder for Kilmarnock in spells - often interchanged with Kiltie while the duo were in Ayrshire.
For Kiltie, the experience has only gone to benefit Taylor as he plays in an inverted full-back role under Ange Postecoglou.
That's not to say there haven't been rocky spells for Taylor - either being sent off for a challenge on Joey Barton or facing the seemingly impossible task of replacing Kieran Tierney at Parkhead.
“He got sent off and left us with 10 men for the rest of the game," joked Kiltie of Taylor's no-holds-barred tackle on then Rangers ace Barton back in 2016. “But definitely, he’s got something about him.
"Greg and Kieran are two totally different players. Maybe the fans we expecting someone to come in and replicate what Tierney provided straight away. That was never going to be the case.
“Greg has gone in and he’s a totally different player, but the way Celtic play right now suits him down to a T.
“(He's) brand new off the pitch. We probably played with each other for the first time when we were only about nine or 10."
Asked where the pair first met, Kiltie sheepishly added: “Rangers - I’m not sure I should say that too loudly!
“So I’ve known him for a long, long time. I know his family really well so I’m delighted he’s doing really well. It’s nice to see.
“We played together when we were younger and then came back together at Kilmarnock when we were both 16.
“We came through together but we actually ended up playing at different times.
“I was playing for the first team but got injured. Then Greg was playing and got his move - which is when I started playing again!
“So I probably missed playing a lot of games together at Kilmarnock.
“But I’m just happy to see him doing well."
With St Mirren the only team to defeat Celtic in domestic competition, Kiltie reckons a few of Postecoglou's players will have the loss in Paisley in their minds before kick-off.
But he's under no illusions over how difficult a task it would be for lightning to strike twice - after all, only Real Madrid and RB Leipzig boast wins over Celtic this season.
"That's not bad names! I'm sure Real Madrid are sitting thinking the same," chuckled Kiltie.
"They're unbeaten in every game apart from the one at St Mirren Park and I'm sure that that will be in a few of their heads.
"It's a massive challenge, and I think we all know that - we are not under any illusions that it's not going to be but we definitely need to believe in our game plan and hopefully we can get something out the game."
