Manchester United will pay Brighton up to £70m for midfielder Carlos Baleba. Michael Carrick struck a chord with many Manchester United fans as he lavished praise on Kobbie Mainoo after his side's thrilling 5-2 victory over Ipswich at Old Trafford, calling the midfielder's performance "immense". Starting in the Premier League for the first time since he surprisingly failed to play a minute at the World Cup, Mainoo caught the eye with his performance and Carrick made sure the 21-year-old was not overlooked on a day skipper Bruno Fernandes scored a hat-trick.

But former United goalkeeper Ben Foster had a different take. "I love Kobbie," Foster wrote on his Threads account. "He's the future, but he's not there yet. Be honest with yourself and you'll know he's not gonna be one of the first four or five names on the team sheet. If he can get a year out on loan where he is the main man, where he is needed and relied upon every single game, that will instil something in him he won't get at Manchester United."

The social media reaction suggested Foster had got it wrong. There are plenty of people who feel Mainoo absolutely should be one of the "first four or five names" in Carrick's side. But, if that was correct, what would it mean for the three international midfielders United have spent more than £150m on this summer after identifying it as a priority area?

New signings Andrey Santos (right) and Youri Tielemans (second right) started alongside each other for the first time against AC Milan in Wroclaw last month. Carrick is about to feel the impact of United's qualification for the Champions League. Last season, United had two midweek games in the second half of the season. They drew at West Ham and lost at Newcastle. They then had 13 and 11-day gaps to their next fixture respectively. Starting with their trip to Everton, United have five games in 16 days before the first international break of the campaign.

If Carrick's side progress in the EFL Cup, they won't have a spare midweek until Christmas. Rotation is inevitable in United's new-look midfield this season - but what will that look like? In assessing the signings that have been made, Carrick speaks about balance. Brazil midfielder Casemiro left at the end of his contract while Uruguayan Manuel Ugarte - likely to leave anyway had he not suffered an anterior cruciate ligament injury during the World Cup - is out until next year. That left Mainoo, Bruno Fernandes and Mason Mount as United's only senior central midfielders going into the summer transfer window, with the latter pair better suited to more advanced roles.

After missing out on Elliott Anderson and Mateus Fernandes, United moved quickly to sign Brazilian Andrey Santos from Chelsea for £48m. A day later, Belgium's 29-year-old Youri Tielemans joined from Aston Villa for £35m. Santos, 22, dovetailed well with Mount during the early pre-season games, sitting deep and screening the back four. Mount played in the number eight role and seemed to be a viable option to stay there into the new campaign until an ill-timed injury at the beginning of August provided a reminder of his unhappy record of absences. Tielemans' pre-season appearances seemed to be based around developing an understanding with skipper Bruno Fernandes.

"Andrey, for such a young man, to come in the way he has, with his character and his personality is a dream," Carrick explained when he spoke to reporters during his side's training camp in County Kildare. "He's so positive, so mature, so switched on; he wants to learn. He comes in and straight away he's trying to help other players, talk in games and communicate. He's got a real substance to him. Youri's a little bit more obvious, probably because we've seen an awful lot of him and we all know him, but again, the character, the personality, the presence, and the quality on top. The two midfielders in particular, will give us an awful lot moving forward."

Michael Carrick was delighted with Kobbie Mainoo's performance against Ipswich. Into that mix has come Carlos Baleba. At £70m, the Cameroon international is in the top 10 of United's most expensive signings of all time. It is the kind of fee, in the club's new era of restraint, that suggests he should also be one of the "first four or five names on the team sheet".

Each player adds something different to United's midfield. Baleba provides speed, aggression, and defensive awareness. Tielemans has comfort on the ball, plus his passing and vision. Santos excels in one-to-one duels. He also has defensive awareness, a good passing range, and used short bursts to break defensive lines. Mainoo's ability comes through his willingness to take the ball in tight spaces and progress it up the field. It is a formidable array of qualities but they cannot all play at the same time.

"You sound like you're in our coaches' office trying to pick the team," said Carrick, when the general plusses and minuses of the situation were put to him before his side's trip to Everton on Sunday. "We're not just putting a squad together for one game on Sunday. We need a squad that's going to take us through the whole season. There's a whole picture in there that we need to balance. Sometimes it's to change during the game, sometimes it's game-to-game, sometimes you play every three or four days. Whoever plays in there, we are talking about adding to the squad and feeling we've got different partnerships and combinations we can rely on to get us through a season with unfortunate injuries or suspensions or whatever may come."

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