Grey came off the bench on the hour and made an instant impact for Lee’s side grabbing the winner at the Suit Direct Stadium to set up a fourth round tie with Premier League side Crystal Palace next month.
Pools boss Lee admitted Grey had been one of the selection headaches he faced going into the game after he impressed on the wing during the Papa John’s Trophy success over Bolton Wanderers earlier in the week.
But Lee had faith the young striker could go on and make a difference in a game that was evenly poised at 1-1 with Grey repaying his manager in an instant.
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“It worked out fantastic. I said to Joe after his performance on Tuesday night [against Bolton] he was very close to starting the game, he was one of the headaches I had even up to probably 10 minutes before the lads came in as to which way I went,” said Lee.
“I just thought I’d go with a bit more of the experience and physicality to start the game. I said that to Joe when I told him he wasn’t starting and that he’ll be coming on and he could impact the game.
“I spoke to him as he was going on and said to him ‘go and get us the winner.’ I didn’t expect him to do it in the first couple of minutes of coming on but sometimes that works out perfectly.
“But Joe deserved his goal from his performances in the last couple of games.”
Grey’s journey to reach the Suit Direct Stadium was unorthodox in that he never came from an academy background.
While some players his age were being snapped up around the region by the likes of Newcastle United, Sunderland and Middlesbrough, Grey remained with the Boys Club at Wallsend and with Cramlington Juniors.
It was not until Grey was able to force his way into trials with Pools before he was picked up by the club.
But Lee, who was aware of Grey’s name when working as part of Boro’s academy, believes his journey is one to treasure and he has praised the 18-year-old for the impact his is making in the professional game at such a young age.
“His name was always mentioned around Middlesbrough. But for someone of Joe's age to be impacting in League Two, I’m not sure how many of the academy lads I’ve had over the years or seen over the years do what he’s doing at this moment in time,” said Lee.
“The academies are fantastic but sometimes we all see lads who sneak under and come in a different way.
“He’s training every week and the last couple of years he’s been training with the first team so that development alone is massive for him.
“He’s holding his own, he’s a fantastic talent and he deserved his goal.”