West Ham have signed Czech Republic midfielder Alex Kral from Spartak Moscow on a season-long loan with an option to buy.
Croatia midfielder Nikola Vlasic has also joined West Ham, from CSKA Moscow on a five-year deal for 30m euros (£26.8m), plus 9m euros in add-ons.
"Alex will provide good competition in the centre of midfield," manager David Moyes said on the club's website.
"He is another young, talented player who we feel has a big potential and will be capable of adapting to the demands of the Premier League.
"We've brought him in on loan initially and, hopefully, over the course of the season he will make a valuable contribution, particularly with our busier schedule of fixtures.