Manchester United completed the signing of Danish defender Patrick Dorgu from Lecce on Sunday for a reported initial fee of £25 million ($37 million).
The 20-year-old has impressed in Serie A over the past two seasons, scoring five goals in 53 appearances in the Italian top flight, and has four caps for his country.
Dorgu is United's first signing of the Ruben Amorim era and should solve a lack of options down the left side for the Portuguese coach.
"I am incredibly proud to be able to call myself a Manchester United player; this is a very special day for my whole family," Dorgu said in a club statement.
“I cannot wait to work with Ruben Amorim; his vision for this team and the future of the club is incredibly exciting.
"There is a clear plan set out for my development, and I feel that Manchester United is the perfect place to fulfil my potential and complete my huge ambitions."
United's ability to back Amorim has been hampered by a need to meet profit and sustainability rules.
But the club's technical director Jason Wilcox is confident Dorgu is perfectly suited for Amorim's preferred 3-4-3 formation.
"Patrick is a really exciting talent; his strong defensive and attacking attributes, adaptability and work-rate will make him a key part of Ruben Amorim’s squad," said Wilcox.
"At the age of just 20, we know he will continue to develop under the guidance of our excellent coaching team."
United are hopeful of raising funds in the final hours of the transfer window, which shuts on Monday.
Marcus Rashford is reportedly on the verge of a loan move to Aston Villa, which will free up the majority of his reported £300,000-a-week wages.
Alejandro Garnacho has also been linked with Napoli but is unlikely to leave before Monday.
