West Ham have signed Stoke City and Austria forward Marko Arnautovic for a club record £20m, which could rise to £25m, on a five-year-deal.
The 28-year-old joined Stoke from Werder Bremen four years ago and was just 12 months into a four-year contract with the Potters.
He scored seven times in 35 games in all competitions last season.
"Everyone knows that West Ham is a big club and I'm happy to be a part of it. I can't wait to get started," he said.
"It feels special to me to be a West Ham player. They are crazy for football and this is what I like. The club is still growing, getting better and better and that's why I'm here."
The Hammers, who confirmed that Arnautovic is their club record signing, previously broke their record last summer when they signed Andre Ayew from Swansea for £20.5m.
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