Carrick took charge in January on an interim basis following the sacking of Ruben Amorim and transformed the club's season entirely, winning 10 of his 15 Premier League matches in charge, collecting 33 points from those games — the best record of any manager in the division across the same period. The run produced Champions League qualification with one game to spare.
Holland joined Carrick's staff at the same time, having previously worked as assistant to Gareth Southgate with the England national team.
His tactical influence has been widely credited internally as a key factor in the turnaround, and United moved quickly to ensure he would remain beyond the initial arrangement. Romano confirmed Holland's deal runs to 2028 with the same option for an additional year as Carrick's own contract.
United's final Premier League match of the season is away at Brighton, where the club will look to finish on a positive note ahead of a summer expected to include significant squad investment.
Champions League football next season gives the club considerably more financial and reputational leverage in the transfer market than was available to Amorim's recruitment team at the start of the current campaign.