THE young Irishman was a snip at £8,000 when he was signed by Frank Hill from Glentoran, and in the eyes of many Burnely fans he is the club's all-time greatest player.
In over 12 years at Turf Moor, he fell just three games short of 500 appearances and scored 131 goals in all competitions.
It wasn't until seven months after signing that McIlroy made his debut, at Sunderland, four days before his 19th birthday, after Harry Potts had moved on to Everton.
Within a year, McIlroy had won his first Northern Ireland cap, against Scotland in Belfast.
With Burnley, he formed a formidable partnership with Jimmy Adamson, which was pivotal to the club's 1960 championship win.
Clarets legend Jimmy Robson described McIlroy as the best footballer he ever played with.
"He was what I call an all-round footballer," Robson said.
"He was a player that could dribble with the ball, pass, head, he had good vision, he scored a good quota of goals and set them up as well.
"He appreciated what he had in the rest of the front line as well."
Burnley official club historian Ray Simpson added: "He knew when a defender was on the wrong foot. Having seen him shift his balance away he would accelerate in the opposite direction, which is a very difficult skill to master.
"It's combining your natural ability with a perception of weaknesses of the opposition.
"He had such an ease of movement. There was no effort involved with it, it all came naturally to him.
"He was a lot quicker than perhaps he was given credit for, but that was because his balance was superb."
The club, and town, was rocked when McIlroy was placed on the transfer list in February 1963 and moved to Second Division Stoke City for just £25,000.
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