Manchester United may have just 17 days to complete critical transfer mission once klaxon sounds

June 14 will mark an exciting day on the football calendar for most this summer. Not only will it signal the beginning of the European Championship in Germany, but it will also mark the opening of the summer transfer window. The shutters will be lifted and clubs will be free to start shopping.

For Manchester United, it is poised to mark one of the most important transfer windows the club has faced in its recent history. For the first time since securing a minority stake earlier this year, Ineos will be governing the recruitment operation, and big changes are expected.

As reported by the Manchester Evening News in February, United are planning to become more proactive in the seller's market, so much so that sales could reach double figures. The exits of Raphael Varane and Anthony Martial have already triggered a potential domino effect.

United need to raise funds through player sales to remain within the boundaries of the Premier League's profit and sustainability rules [PSR], meaning one or two big-name stars may be moved on. The likes of Harry Maguire, Scott McTominay and Casemiro are by no means safe from being axed.

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But as important as it will be for the club to oversee a clear out this summer, they still need to bring in new faces, both to strengthen the starting XI and improve the level of depth. United have already identified a handful of positions they intend to strengthen as a bare minimum.

Among them, of course, is the centre-back department. United have already said au revoir to Varane, who has left the club after three seasons at Old Trafford, and