Southampton wasted no time making defender Jan Bednarek the club’s first signing of the summer whilst extending the contracts of Jack Stephens and Sam Gallagher.
Bednarek, who joins Southampton from Lech Poznan on a five-year deal, competed in the Under-21 European Championship with Poland.
Les Reed, Southampton Vice Chairman, said: “Jan is an extremely promising young player who possesses significant potential.
“We are delighted to bring him to the club, and we believe this will be the ideal place for him to continue his development.”
Bednarek was a mainstay in the Lech lineup that finished third in the Polish top-flight in 2016/17.
He said: “I think it's a good step for me, because I have heard Southampton is such a good club for young players, so I can improve here. I think it will be a good move for me.”
Stephens and Gallagher, meanwhile signed five-year and four-year deals, respectively, to remain at the club.
Stephens had a breakout end to the season replacing the injured Virgil van Dijk in January.
He said: “It feels like home to me. I have really enjoyed my time here and am now looking forward to the next five years.
“It’s a massive platform for me now because it just shows how much faith the club have put in me.”
Gallagher looks to break into the squad after a successful loan spell at Blackburn Rovers where he netted 12 goals in the Championship.
The 21 year-old made 20 total appearances for Southampton between 2013 and 2015. before spending consecutive seasons on loan.
He said: “It shows the belief that the club have in me and I need to prove that now, which is what I am hoping to do in pre-season.”