Slaven Bilic claims keeping hold of Dimitri Payet is a statement of West Ham's intent ahead of the new Premier League season.
France international Payet's displays at Euro 2016 saw him linked with a move to some of the world's biggest clubs.
But the Hammers have kept hold of their star man as they begin life in their new 60,000-capacity London Stadium.
"In keeping Dimitri Payet we have shown the club is serious and trying to get to another level, as much or even more than with the new stadium," West Ham boss Bilic said.
"West Ham was always labelled as a club that has to sell its best players, be it Frank Lampard, Rio Ferdinand or whoever. But we have kept Dimi, and we have shown to everyone that the club is thinking seriously."
Bilic has also made some eye-catching new additions to his squad including Algeria winger Sofiane Feghouli, Norway midfielder Havard Nordtveit and, earlier this week, Swansea striker Andre Ayew.
Ghana international Ayew cost a club-record £20.5million and Bilic feels the 26-year-old, who scored 12 Premier League goals last season, will have a major impact in east London.
"First and foremost he was (previously) at a big club at Marseille," added Bilic.
"He's an international, he's the captain of Ghana, he's at his best age and he's already had a year in the Premier League so it's nothing new to him.
"Players today make you feel at home after just a few days so I'm sure we can expect some good football from the newcomers straight away."