The signing of scamacca is a deal worth over 35 million dollars.
The Italy international has signed a five-year contract with the option of a further year at the London Stadium.
The Hammers have agreed to pay a sum of money. There is a 10 per cent sell-on clause for the Italians.
"I'm really excited to join West Ham, I've been given the number seven shirt," said scamacca. It has been a dream of mine to play in the premier league.
West ham is the perfect team for me. When I talked to the manager, he understood that they really wanted me. I hope we will love each other and I can't wait to show the fans what I can do.
"We've been looking to add more strength to our attacking options for a long time, so we're delighted to have got Gianluca in," David said. We're excited to work with him. He is a young center-forward with a bright future.
The signings of Alphonse Areola from Paris Saint-Germain and Flynn Downes from SWANSEA City made West ham's fourth summer signing.
It's not out of the question that West ham will sign both scamacca and broja, but it's more likely that they'll sign one or the other.
The Irons have made a bid for Lille's Amadou Onana, and they are keeping an eye on the situation at Napoli, as well.
Ahead of a season that will see West ham improve with a first Europa Conference League campaign, David Moyes wants to improve his squad.
After Scamacca's arrival, West ham will work on a deal to sign Kostic.
The 29-year-old can play as a left wing-back or as a left winger and the Hammers have offered an initial 10 million with add-ons.
The Serbia international likes West Ham and has a lot of respect for the club, but he's not sure if he'll join because he's guaranteed a place in the European Championship with Eintritt.
The left-back position has been a priority for the club this summer and they have signed Kostic.
Kostic had a close look at the Hammers last season as they lost to Eintracht in the semifinals of the Europa League.
Kostic had the most assists in last season's tournament with six, and he won the player of the season award.
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West Ham are looking at a number of players this summer, and one of them is Ben BreretonDiaz.
The Championship side is thought to want around 15 million dollars for the 23-year-old, who is entering the final year of his contract at Ewood Park.
In 37 Championship games, BreretonDiaz scored 22 goals.
It's easy to see why Gianluca scamacca has been in demand. He scored 16 times in Serie A last season and is capable of many more. He took the route to the top.
Scamacca is both an early and late bloomer. When he was a teenager, he traveled to the Netherlands twice in order to find an opportunity. At the age of 21, he was out on loan at Ascoli.
He is seen as the man around whom Italy should build their attack, as well as a man who could be Zlatan Ibrahimovich's heir. A man is dancing.
Here, you can read Adam Bate's profile.
The transfer window will close at 11pm on September 1st.
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