Ralf Rangnick believes Manchester United should focus on signing younger players as the interim Red Devils manager outlined his transfer strategy.

Rangnick will take charge of his first match when United welcome Crystal Palace to Old Trafford in Premier League action on Sunday.

The 63-year-old has been appointed until the end of the season, with former RB Leipzig boss Rangnick set to move into a consultancy role until 204.

Rangnick has earned a reputation for identifying young talent during his work with Red Bull-owned clubs Leipzig and Salzburg and as the January window approaches, he provided an insight into how he operates.

"One does not exclude the other. The team has, with Mason [Greenwood] and Marcus [Rashford], two players who are homegrown and have come from the youth ranks," said Rangnick after United signing 36-year-old Cristiano Ronaldo and 28-year-old Raphael Varane ahead of the 2021-22 campaign, having also lured Jadon Sancho, 21, to Manchester.

"It's about recruitment but also at a club like Man United, with a top academy, we should make sure that every year we have one or two players who are good enough to make it into the first team.

"On the other hand, with signing players for transfer fees, it's a question of what you want. If you pay big money for a 30-year-old and he's still good enough to make you successful, I don't mind that.

"But you have to be aware the money you invest is only being invested in the potential success over the next two or three years, you won't get any return.

"This is where I always think it always makes more sense to sign a player at 21 or 22 and if you then have to pay a big fee, at least you have the chance to develop him into a player who is worth even more."

At Leipzig, after spells with the likes of Hoffenheim, Hannover and Schalke, Rangnick – known for his high pressing – took charge of the team in two different spells, having initially joined parent company Red Bull as director of football in 2012.

Under Rangnick's leadership, Leipzig had gone from the regional league to Champions League qualification by 2017.

Rangnick – who will become only the sixth German to manage in the Premier League – was promoted to the head of sport and development for Red Bull in 2019, before eventually joining Lokomotiv Moscow earlier this year.

Rangnick has never managed outside of his native Germany, taking charge of five different teams in the German Bundesliga in his career. The last side he managed was Leipzig, winning promotion with them from 2.Bundesliga in 2015-16 before returning to the club for the 2018-19 top-flight season and leading them to third place.

Across 294 Bundesliga matches, Rangnick has a winning percentage of 41. He first took charge in the top flight in May 1999 at Stuttgart, losing 2-0 to Bayern Munich, while his last game in charge in the competition came 20 years later in May 2019 at Leipzig, a 2-1 defeat to Werder Bremen.

His best top-flight finish as a coach is second, achieved in 2004-05 with Schalke, a side he took over mid-season and led to a runners-up position and also to the final of that season's DFB-Pokal, ultimately losing 2-1 to Bayern.

Compared to countryman and Liverpool manager Jurgen Klopp due to their high-octane brand of football, Rangnick addressed the comparisons.

"Well my football is definitely not a slow waltz!," said Rangnick, whose United have already been linked with Leipzig pair Christopher Nkunku and Amadou Haidara. "I am not that far apart from Jurgen in terms of our ideas about a style of football. That’s no secret.

"But you have to be aware of what kind of players you have and where they stand. I cannot ask things of them that they can’t deliver right now.

"I have to take them and accept where they currently are. They are experienced and smart enough to know that. I cannot turn the players we have into the pressing monsters I want them to be within two, three or four weeks.

"The same happened to Jurgen when he came in the middle of the season and they finished eighth or ninth. Liverpool had a lot of injuries in that time - muscle injuries - because they were not used to that kind of training. So we have to be smart."

United are seventh in the Premier League standings and 14 points adrift of leaders and defending champions Manchester City.

The Red Devils have conceded in 15 consecutive home games in all competitions, their second-longest ever such run, after a 21-game streak ending in March 1959.

Rangnick added: "I am more than optimistic, but I also have to be realistic. Five weeks ago, our team lost 5-0 against Liverpool - and it could have been a lot more if we are honest.

"Against City it was 2-0 - but it could also have been more. It was important to win the point at Chelsea but the performance? I don't know. They had 24 shots on goal and we had three.

"So right now, to say I will challenge the top Premier League managers in the next few weeks or months, is not realistic. Right now my focus is on Crystal Palace and then on Young Boys, then Norwich, then Brighton and Hove Albion and then Brentford.

"The games against Chelsea, Liverpool and Man City will be in March and April - and that’s when I will answer the question about challenging them."