Arsenal have signed Benfica defender Nuno Tavares for a reported $9.5 million fee.
The 21-year-old left back will provide coverage for Kieran Tierney.
“Nuno’s arrival will give the squad extra strength and options in defence, particularly with this energy on the left side of the pitch," said Mikel Arteta.
Arsenal are also close to a deal for Anderlecht midfielder Albert Sambi Lokonga.
They have reportedly agreed to pay an initial fee of $20.7 million.