Heading into this knockout tie, the young Reds have won six games in a row - netting 22 goals in the process - and after Monday night's 4-0 win over Accrington Stanley in the FA Youth Cup confidence is high.
However, United beat the Reds 3-1 in the second game of the season in Kirkby and Lewtas insists his players learned a valuable lesson that day.
Kick-off at the Academy is at 11am GMT and you can watch the game live on LFCTV GO with our single-camera coverage.
Read Lewtas' thoughts on the clash, the recent good form of his side, and players getting their chance to move up to U23 level, below...
On Monday night's 4-0 win over Accrington in the FA Youth Cup fourth round…
We knew they would be tough coming into the game on the back of a fantastic result against Leeds United. We knew they would raise their game against us because a lot of their boys are from Liverpool. It always helps when you get the first goal and Rhys Williams loves scoring at St Helens! We always put good balls into those good areas and Rhys is a real threat when he comes forward like that. I'm pleased for him as it could become a useful part of his game. That goal probably settled a few nerves and then we kicked on in the second half. They came at us a little bit more, which created more space and gaps and it made it a little bit easier for us, so it was pleasing and we now look forward to the next round when we host Wigan Athletic in another tough game.
LFCTV GO: Watch the Accrington action
On captain Paul Glatzel netting his third hat-trick of the season…
It was fantastic and everybody was pleased for him. It was the perfect hat-trick - a header, right foot and a left foot! That's what goalscorers do and fortunately for him and us he managed to get three on the night.
On facing United in the Premier League Cup quarter-final…
It's a fantastic game to look forward to and we can't wait for it. With it being a quarter-final tie, it adds a bit extra to it but, to be honest, if it was a pre-season friendly against United it would be a big game and both teams would take it seriously! The boys have had a good week and we have worked hard in training. We know we are in for a tough game and I'm sure they will be expecting the same from us, so hopefully it will make for a really good game.
On his message to his players ahead of the game…
I think it's important that we try to impose our game on the opposition. They have a way of playing and have a nice brand of football, so we know what to expect. We need to be better than what we were against them in the second game of the season out of possession.
On that 3-1 defeat by United in Kirkby back in August…
It was our second game of the season and it was a close game. We were trying to get the equaliser and then they scored a stoppage-time penalty. It was a game that overall we were all a little bit disappointed with our levels. If you are not quite at it and you don't do certain things properly then you can't really argue if you don't win the game. We were gracious in defeat but what was interesting about that game was the way we responded when we went down to 10 men. Maybe that was the beginning for the character the boys have shown throughout this season, scoring late goals and sticking together. When we played the final 25 minutes with 10 men I actually thought we were a real threat. It was just a shame it took the red card to get us going.
On trying to use home advantage on Saturday morning…
Of course it can make a difference. I think this is one of those games we would play it anywhere, even if there was a local park free. These are big games even at Academy level, we are excited to host it and if it gives us a little advantage then great. It's important to make sure we are right at it right from the kick-off.
On Abdi Sharif making his first start for the U23s and providing an assist during the 2-0 win over Swansea City on Thursday night…
I was pleased for Abdi. I've said all along that is the aim. We want to try to move our boys up to the U23s and that has been the idea since day one. He certainly contributed to the game and imposed some of his strengths with the assist. It was also nice for Rhys and Bobby Duncan to come on as well. I've said to the boys that is the aim and try to contribute when you are needed, whether that is from the start or from the bench. Abdi played 85 minutes on Monday and 90 minutes on Thursday, so fair play to him.