Manchester United have been left surprised as Foster and Partners, the architects set to construct their new 100,000-seater stadium, have also agreed to revamp the San Siro. Concerns are said to be mounting over whether the London-based firm, which lacks offices in Milan or Manchester, can handle two colossal projects simultaneously.
Sir Norman Foster's ties with Sir Jim Ratcliffe were instrumental in securing the contract for the Red Devils' future home, expected to cost around £2billion.
Foster has estimated a five-year timeline for the project, but with the addition of the iconic Italian stadium to their workload, City AM reports rising anxiety about the firm's capacity to juggle both tasks.
The Premier League heavyweights announced their intention to vacate Old Trafford for a new 100,000-seater colossus in March.
Set to be the UK's largest stadium, it will be erected on land adjacent to their current ground. Ratcliffe has expressed his ambition to erect "an iconic football stadium".
He stated: "By building next to the existing site, we will be able to preserve the essence of Old Trafford, while creating a truly state-of-the-art stadium that transforms the fan experience only footsteps from our historic home."
Ratcliffe highlighted the regional imbalance in football infrastructure, arguing: "The north of England has won 10 Champions League medals, London has two. But London has Wembley, Twickenham, Wimbledon and the Olympic Village.
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"The north of England deserves a stadium where England can play football, where we can hold the Champions League final, and one befitting of Manchester United's stature."
United's stadium ambitions are in the embryonic phase, with visionary videos and early images circulating, rather than concrete schematics.
Meanwhile, over in Italy, AC Milan and Inter Milan have put forth their commitment to give the iconic San Siro a facelift, despite its historical prestige and having played host to a Champions League final as recent as 2016.
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The protracted tale of the Milanese venue's redevelopment continues apace.
In 2019, a previous proposition for a new 60,000-seater stadium, named "Cathedral" and inspired by the famed Duomo, was scrapped after failing to secure support from city officials.
The decision compelled Milan and Inter to scrap their plans for independent stadiums and they instead united last year for a collaborative refurbishment project on the hallowed grounds of the San Siro.