Southampton have broken their transfer record to sign Moroccan attacking midfielder Sofiane Boufal from French side Lille for £16m.
Boufal, 22, scored 11 goals last season to help Lille finish fifth in Ligue 1 and qualify for the Europa League.
Southampton's previous transfer record was the £15m they paid Roma for forward Dani Osvaldo in 2013.
"I can see that this club is the best place for me to continue my progression as a footballer," Boufal said.
Les Reed, the club's executive director of football, said: "We are extremely confident he will successfully adapt to life in the Premier League.
"Sofiane is a player we have watched develop closely over the last few years, and we're thrilled to have him join the club. We're delighted that Sofiane sees Southampton as the best place for him to continue his development."
But he added the player would be some weeks away from a first-team appearance while he gets up to match fitness.
Boufal, who has signed a five-year contract, is the latest summer arrival as new manager Claude Puel shapes his team following several departures.
The Frenchman replaced Ronald Koeman in June after the Dutch manager left to join Everton.
Sadio Mane, Victor Wanyama and Graziano Pelle all left the Saints during the summer for combined fees of £57m.
Southampton spent £10m to sign Nathan Redmond from Norwich City while Pierre-Emile Hojbjerg arrived for £12m from Bayern Munich.
Meanwhile full back Jeremy Pied, a summer signing from Nice, says he needs an operation on a knee ligament injury.
The 27-year-old told his Twitter followers: "I can confirm the bad news for my knee - I need an operation.
"It's hard to digest but it's a trial to overcome. I'm determined to give all my energy to come back as soon as possible on the pitch."