West Ham have completed the signing of Mexico international Edson Alvarez from Ajax for an undisclosed fee.
The 25-year-old has agreed a contract until June 2028 with the Europa Conference League winners.
He strengthens the Hammers' midfield options following the sale of former captain Declan Rice to Arsenal.
West Ham manager David Moyes told the club website: 'The midfield area was one we were especially keen to strengthen this summer - and Edson will complement the other options we have in that department.
'He's an experienced international player, who has enjoyed great success for both club and country during his career to date.