The young Magpies travel to the Lamb Ground aiming to continue their positive start in the competition after claiming a 2-1 comeback against FC Halifax Town in their opening Group C fixture last month, with away clashes against Boston United and Gateshead also to come after taking on last season's National League North champions.
Newcastle's youngsters face a Tamworth side who knocked out League One outfit Huddersfield Town in the Emirates FA Cup first round, with the winning goal caused by Tom Tonks' dangerous long throw-in and Harris, who signed his first professional contract with his boyhood club last summer, is keen to avoid a similar situation himself should the central midfielder feature against United's second-string.
The 17-year-old shot-stopper, who joined United's youth set-up in 2017, told newcastleunited.com: "I think you need to treat them as a corner coming into the box, being on the front foot and making sure that everyone is picking up their men so there's no free headers. That could be a big test and we'd have to adapt to be able to face that problem.
"We're excited for the game. It's always a different challenge, facing these kind of teams and playing on their pitch. We saw the result last week and they're a good team coming off the back of a big win. We're all really eager to play them.
"Anytime you play against a men's team, it's always going to be physical and, as a goalkeeper, you know you'll be facing balls into the box and know what to come up against, no matter what the team is going to be. We need to have the right mindset of winning our own duels and battles."
Newcastle's second-string recorded an impressive 3-1 away win against Leeds United in the Premier League 2 on Friday, with Sean Neave, Charlie McArthur and Ben Parkinson all on target to help the young Magpies secure a third win in their last four away league matches.
Harris reflected positively on last week's victory against their Whites counterparts and believes a number of bright performances shown on the road so far this term have benefited Diarmuid O'Carroll's side.
"The team performed very well and managed to score three great goals," he added. "We were good in possession and did even better out of it to be able to hold them off towards the end, putting our bodies on the line with some big blocks.
"It's about being consistent, creating chances in away matches as well as at home, and making sure you put those chances away. It builds confidence for away games we play. It's always a good training day at the Academy with all of us together, especially when it's the day before a matchday when we have small-sided games.
"Being able to have so many players in the squad is good for us to switch it around for these types of periods where we have a few games. Everyone is respectful for that and it's good for all of us as a team."
Tickets for Newcastle United Under-21s' National League Cup Group C clash against Tamworth on Tuesday, 5th November can be purchased here.
Please note all tickets for those aged 17 years and under MUST be purchased online in advance of the game (Tickets remain on sale online up to 7.45pm on a match day).
There will be NO tickets for sale for any young person aged 17 and under in person from Tamworth's Matchday Ticket Office at the ground on the day of the game unless the young person is accompanied by a paying adult. This applies to both home and away supporters.
