Leeds have their first silverware for 28 years without kicking a ball after being crowned Sky Bet Championship winners.
Marcelo Bielsa's men saw their 16-year Premier League exile end on Friday as West Brom lost at Huddersfield and were then upgraded to champions as Brentford were beaten at Stoke.
The West Brom result sparked a night of celebration at Elland Road and Leeds will take the party to Derby on Sunday for their penultimate game of the season.
"They are part of a great legacy that we will work hard to honour, as we continue to take strides forward in a new cycle for this fantastic club."
Radrizzani assumed sole control of Leeds in 2017, having initially gone through a staged buy-out from the unpopular Massimo Cellino.
After a false start under Thomas Christiansen and then a short spell under Paul Heckingbottom, he and director of football Victor Orta pursued Bielsa to be their next manager.
"Marcelo deserves all the accolades he gets. He's got the club back in the Premier League and it's not been an easy task as previous managers have found out," Leeds great Eddie Gray told the Yorkshire Evening Post.
"The club has been through some difficult times but now we're sitting at the same table as the big boys."
Howard Wilkinson, the last Leeds manager to win a trophy, added on the BBC: "They'll bring a lot to the party, if they do well. They'll add to the attraction of that league, which is now a worldwide league in terms of spectators."
