Tom McCartin not only stunned a packed SCG when he jagged the late go-ahead goal in Sydney’s thrilling two-point victory over Collingwood on Saturday night.

The youngest player in the AFL stunned himself.

McCartin touched the football just six times in the game but arrived on the scene when it mattered most, connecting a desperate boot with the Sherrin while sprawled across the turf with just two minutes left on the clock.

Although the master at work in the epic final minutes, the 18-year-old was left as baffled as the 39,238 onlookers.

“I kind of just banged it on the boot and it somehow went in,” McCartin told SwansTV post-match.

“It was a great win by the boys and we fought really hard and I was lucky enough to get on the end of one in the last couple of minutes.

“I kind of just kicked it and I didn’t know what I was doing. I just ran off because I didn’t know whether it was touched or whether it went in. Luckily it went in and it was a great feeling.”

Although just 11 games into his AFL career, McCartin has played a part in a number of heart-stopping finishes.

He debuted in Sydney’s last-gasp eight-point win over Hawthorn in Round 8 and helped the Swans to the come-from-behind six-point victory over the Kangaroos in Round 17.

But if the words of the towering key forward are of any indication, Saturday’s at-the-death win over Collingwood matched the best.

“They’re pretty special wins those ones,” McCartin said.

“We fought really hard and especially in that last quarter and came away with a great win.

“It was pretty tense but we kept our composure and ended up hitting the lead in the last couple of minutes.”

Evergreen Magpie Travis Varcoe ran into an open goal to hand his side a five-point buffer five minutes out from the final siren.

But the Swans, despite having absorbed waves upon waves of pressure in defence throughout a gripping final quarter, would work the football forward.

Tom Papley slammed the ball inside 50 in pursuit of Lance Franklin, the Sherrin spilled to ground and McCartin – on a second attempt amid frantic congestion – produced the heroics.

The Magpies surged inside 50 in the shadows of full-time, but Isaac Heeney would mop up and the Swans held on for the win.

It made for an unforgettable night for inspirational defender Alex Johnson, who returned for his first senior match since the 2012 grand final.

Five knee reconstructions, seven other knee surgeries, a recurring knee infection and a recent groin operation had denied him an AFL game for 2136 days.

But the 26-year-old looked at ease in his 46^th AFL appearance, manning up on imposing Collingwood forward Mason Cox and holding his own.

Johnson kept the American import to one goal, collected 15 possessions and 11 marks and was admirable in his ball movement out of defence.

McCartin was in awe of his never-say-die teammate.

“It was unbelievable to run out with him,” McCartin said.

“He’s got such an amazing story. He’s inspired everyone, especially me, with what he’s done and what he’s been through. It’s an absolute credit to him and he did so well tonight. It was all very special.”

McCartin also tipped his hat to the raucous cheers of the red-and-white faithful.

“The crowd’s support was huge, especially in those last couple of minutes,” McCartin said.

“The noise was unbelievable, it was a big crowd and it was a great turn-out for a great win.”