Within a year, King had made his first-team bow for the Canaries and been called up by Scotland Under-21s. He marked the latter by scoring a late equaliser on debut against Switzerland.
Then, though, came the hard times as his career at Carrow Road stalled. A parting of the ways followed in 2016, along with a drop down to level nine of the football pyramid with Thetford Town.
Moves to Shamrock Rovers and King’s Lynn Town hardly suggested a major turnaround in fortunes was imminent but today will bring a welcome return to those heady days when the Cup spelt glory for King.
FC Halifax Town host AFC Wimbledon in an FA Cup second-round tie that will be beamed live to the nation by BT Sport. And King, who moved to The Shay during the summer, cannot wait.
“Being live on the telly is a big occasion for everyone,” the 23-year-old, scorer of Halifax’s winner in the last round against Morecambe, told The Yorkshire Post.
“I didn’t realise until after the last round that it was the first Football League team FC Halifax had beaten. That gave me a very proud feeling.
“Was I surprised? No. We have a good squad here. We maybe have not shown that enough in the league, where our results have not been consistent enough.
“But I felt we showed against Morecambe what we can be about. Everyone worked their socks off. Now, we want to have a right good go at Wimbledon.”
The live cameras will be making their third Cup appearance at The Shay since FC Halifax emerged from the ruins of the old bankrupt club a little over a decade ago.
Charlton Athletic in 2011 and Bradford City three years later ensured neither ITV nor BT Sport got the shock that television companies crave in the world’s oldest knockout competition.
Whether the Shaymen can make it third time lucky this lunchtime remains to be seen but the clash with League One Wimbledon will, at least, provide King with a chance to once again savour some Cup glory.
“Winning the FA Youth Cup at Norwich was incredible,” he added. “We had some good players in that team. A lot went on to play in the Premier League.
“There were Josh and Jacob (Muprhy), the twins. One is at Newcastle now, the other Cardiff. Cameron McGeehan is at Barnsley. In fact, Carlton (Morris) is the only one still at Norwich from that Youth Cup winning team, which is a little bit crazy.
“We beat Chelsea in the final. Carrow Road was packed for the first leg (which Norwich won 1-0) and then we took around 4,000 fans to Stamford Bridge for the second leg. They sang all the way through and the celebrations at the end were brilliant.
“You only have to look at Chelsea’s record (the Blues have lifted the trophy in six of the last seven years) to see what talent comes through there. The team we played in that final was incredible and have gone on to big things.
“But we are the last team to beat Chelsea in the Youth Cup. I am still proud to have been part of that.”
King’s solitary appearance for Norwich’s first team came in the League Cup at Shrewsbury Town. He admits to finding life tough after finally calling time on his stay at Carrow Road.
“Leaving Norwich was difficult,” said the midfielder, whose departure came at a time when he was troubled by migraines. “I had been there 10 years. It felt like home. To then leave, your confidence goes. You just want to get back on your feet but it is hard.
“You move from club to club, often struggling to settle in.
“Most footballers go through that, coming from top teams and then having to work their way back up.
“That is part and parcel of football. I know that. But coming to Halifax was a fresh start at a good club.”
King’s winner in the last round against Morecambe means he has already justified the faith of manager Jamie Fullarton in bringing the midfielder north from King’s Lynn, who play two levels below Town.
Now, he wants to help create another slice of history as FC Halifax attempt to break new ground.
The club’s best run in the FA Cup came a couple of years ago when a first round replay win over Dagenham & Redbridge was followed by a disappointing home defeat at the next stage to Ebbsfleet United.
“Getting into the second round is massive for everyone at the club,” added King, whose strike earned the Shaymen a six-figure windfall that includes a £75,000 broadcast fee for today’s tie.
“We felt we did enough in the first game against Morecambe to win but we were excellent in the replay.
“They came at us in the second half a bit, as you would expect. But we ground out the win. The back four were brilliant, putting their bodies on the line.
“It was not just the defence, either. Defending does not just happen at the back. It is the whole team. We worked our socks off.
“We know it will be even tougher against Wimbledon, who are from the division above Morecambe.
“Playing a team from a higher division is never easy. Sometimes, you have to soak up a lot of pressure. We did that and it was a great performance from us.
“The thing is we have played a lot better than that. But not got the results.”