The youngster has impressed for the Magpies so far this season, despite not yet making a Premier League start.
But the Newcastle manager could be willing to play Armstrong against Tottenham tonight - even from the start.
“I thought he did well against Crystal Palace and Manchester City in terms of the role he had," Pardew told the Newcastle Evening Chronicle. "He’s a player that I have a fantastic expectation on and whether he gets a start we will have to wait and see.”
The Newcastle boss, however, admits the majority of the side he puts out to face Tottenham will be 'very strong.'
“These are the only competitions where you can look at players with hope and ambition because in the Premier League it’s difficult.
"We have played two Premier League teams in this competition but it has paid off massively for me and I feel very confident about the whole group. Having said that we will be very strong at Spurs.”