The young midfielder, still just 19, was on the bench for the first time on first team duty against Liverpool at the weekend.
The England youth international didn't taste the action at the Lane but, with one game left at Filbert Street, you never know.
'Jacko', who overcame tendonitis in both knees earlier in the season, reflected: "Just to be out there warming up, with the anticipation of the crowd, it's something I've not experienced before with the first team. It was a great feeling.
"It's a big step for me. I haven't made my debut yet but that's what you dream about when you are growing up, so being on the bench is the closest I've been to that debut.
"Just being on the bench means you've got a chance, you could come on, you never know. It's a big confidence booster, definitely."
Did the heart race any faster as he was warming up? "I've got to admit the heart was beating a little faster at times, especially when myself and Doc were told to warm up," he added. "But we were playing well and winning 1-0 so I couldn't see the manager changing it anyway."
If Jacko needed any reminding of the massive challenge to break through at a club like Spurs he has got just that in the last fortnight with the arrival of Jamie Redknapp and Milenko Acimovic - two more midfielders in his favoured position.
He pondered: "You know what you are up against to break through at a club like this.
"Jamie Redknapp is another quality player and what the club needs. It's just good to be training with players like that, Jamie, Gus, Darren who all play in the same position, you learn off them all the time."
John Jackson has taken another significant step up the ladder that he hopes will soon lead to a Premiership debut.