The 28-year-old has become the Irons' fifth signing of the summer after the arrivals of Ryan Fredericks, Lukasz Fabianski, Issa Diop and Jack Wilshere, and the Manuel Pellegrini revolution appears to be in full swing.
Yarmolenko has been getting to know his new surroundings over the past 24 hours, and took some time out to sit down and discuss the man he'll be playing under next season.
As quoted by the club's official website, he said: "I have spoken to Manuel Pellegrini. We had a short discussion about how he sees us playing and how he wants to use me on the football pitch.
“He comes across like a very kind and good person to me. Of course, he has coached some great clubs across Europe as well, so I am very interested to begin working with him.
"I know I am the fifth player to arrive at West Ham this summer. I can see that an interesting project is being built here and that the team has very high aims that they want to achieve."
Those comments must make for an encouraging read for the supporters, who are seeing an exciting rebuild going on at their club after the toxicity of last season.
Clearly Pellegrini's nature and credentials are a big factor behind why players want to come to the London Stadium, and he is being backed by owners David Gold and David Sullivan. The Daily Mail report that the Hammers are closing in on another transfer target, Lazio star Felipe Anderson for £40 million.
Together they are all working to build a new project, and it will be interesting to see now if the Chilean can get these quality players to gel.