Following the arrivals of Tyrell Malacia and Christian Eriksen, Manchester United finally confirmed they had captured Ajax's versatile defender Lisandro Martinez on Wednesday. The Argentine has cost the club an initial 46.8million which could rise to 55.3million if certain clauses are met.
United's new No.6 has signed a lengthy contract until 2027, with the option of a further 12 months, but his acquisition now means the club has seven senior centre-backs in the squad as well as their promising youngsters. Phil Jones and Axel Tuanzebe may both be moved on after entering the final year of their contracts and Eric Bailly could still leave too, with recent reports linking him with a move to Roma and a reunion with Jose Mourinho.
Even if they do depart, Ten Hag still has plenty of centre-back options to choose from as well as six different full-backs in Malacia. Diogo Dalot, Aaron Wan-Bissaka, Luke Shaw, Alex Telles and Ethan Laird. That's a lot of players to choose from and it will be interesting to see who the new manager settles on as his first-choice defence.
MEN Sports writers have debated who they believe should be in the back line below:
In an ideal world, Raphael Varane would start every match for United next season, but the hard truth is he can't be relied upon often enough and has to be considered a high-quality back-up rather than a regular starter at the beginning of the season. Harry Maguire has looked good in pre-season with his distributional play and, given he is still the club captain, it seems certain that he will be one of the two starters next season.
His struggles are partly down to a lack of a regular, reliable partner and the fact that he has been played out of position on the left. Both of those issues should be solved by the arrival of Lisandro Martinez, whose style of play should compliment that of the United captain.
At full-back Diogo Dalot has moved ahead of Aaron Wan-Bissaka on the right and Luke Shaw remains the best option on the left despite competition from Tyrell Malacia.
Martinez looks to be a very canny signing, who ticks all the boxes and will surely play a massive part in United's future. But, at present, as he remains untested in the Premier League, Varane is still United's best centre-back. After adapting to English football, Varane began to find his stride in a poor United team and actually managed to forge a decent partnership with Maguire.
The only problem is that they didn't play together enough due to his proneness to injury. That has continued in pre-season and it doesn't look optimistic for the season but if Varane is fit he should certainly be the first-choice. It will be up to Martinez to prove himself and take advantage when the Frenchman is inevitably sidelined.
Dalot looks to have corned the right-back spot for the campaign but left-back is still up in the air. It's Shaw's for now but if he doesn't get back to his best then Malacia will be on hand to take it.
The perfect scenario for Ten Hag would be to have Varane available for every game. A calm, composed figure who is equally adept at doing the rough stuff needed against some Premier League sides, he also knows what it takes to win as underlined by his glittering CV for club and country.
This is a man who has won four Champions Leagues and the biggest prize of them all with France. United have splashed the cash for Martinez and, given that transfer fee and the fact Ten Hag knows him, it would be no shock to see him become first choice at centre-back. Maguire and his struggles have been well-documented, but his form at international level should not be overlooked either and that success has come alongside another accomplished man on the ball; John Stones. Maguire and Martinez could provide a similar blend for Ten Hag.
Dalot might encounter competition further down the line, but has done enough to be given first dibs at right-back. Malacia and Shaw ought to be a compelling battle and the former also gives United scope to switch things up and deploy a wing-back system. Shaw for now, but the question might have a different answer further down the line when Malacia had settled into his new environment.