The young Magpies take on the German outfit at Whitley Park on Wednesday night (7pm GMT) and must defeat Hertha's reserve team in order to keep their chances of advancing into the quarter-final stages on track.
After a 1-1 draw in their opening Group C clash against Benfica, Newcastle's youngsters must win their remaining two fixtures against Hertha Berlin and Blackburn Rovers, with only the top teams automatically progressing into the knockout stages.
Sangare, 20, told nufc.co.uk: "We need to win the game. We've gone two or three games now without one so we need to get back to winning ways and restore some confidence.
"It's never nice to lose and I think a win would be very important for everyone as we want to be playing for something.
"The teams we are playing from different countries give you something different and something to look forward to. Playing in the league 24/7, you know what to expect in being physical. With these teams, it is a bit different as you have to be switched on all the time and not fall into any traps.
"I think getting the win would give us a great chance to finish top of our group. After drawing against Benfica, we know how important this game is going to be and how well we need to perform as a team. We haven't had the best of performances in recent games but I think it will be a lot better if we can get a victory.
"From the Benfica game, it was one of those games where we had to stay in it. That's the mentality we've got built up; if we can't score, we should make they cannot score at the other end."
United's second-string did not participate in last year's competition but did reach the semi-final stages in 2018, with Sangare featuring as a substitute in Newcastle's 1-0 defeat to eventual winners Porto.
The midfielder, who made his senior international debut for Liberia in March, is determined for the squad to end 2019 on a positive note.
"I played in the tournament two years ago and I know what to expect," Sangare added. "With the younger lads coming up, I think they need to be aware and can learn from these games.
"We got the semi-finals and going through the games, you can tell the teams have got different abilities about how they play. Playing in different competitions give you a lot of things to look forward to. It helps the team and builds a certain confidence.
"Getting some strong results before the year ends would be the best feeling ever. It's my birthday at the end of this month too but knowing we are doing well would be a good feeling and something to go away with and look forward to coming back to in the new year.
"This game is just as important as every single game we play this season."
Tickets for the game at Whitley Park are available at the turnstiles, priced at £3 for adults and £1 for concessions. Admission is free for season ticket holders and members.
