Joao Mario is keen to revive his career at West Ham United after completing his loan switch to David Moyes' side from Inter Milan.
The 25-year-old Portuguese midfielder will remain with the Hammers until the end of the season.
Moyes has added Mario to his squad as Manuel Lanzini and Marko Arnautovic are currently injured.
"I am really happy to be here," Mario told the club's official website. "It's a really amazing experience to join this amazing team and I am just glad to be here.
"It was a fast move. I have spoken with everyone around the team and, for me, it is exciting to play in the Premier League. I spoke with the coach and for me, I am really happy to be training for an amazing coach."
Mario scored three goals in 47 appearances for Inter following his transfer to the Serie A side from Sporting Lisbon in the summer of 2016.
He has 31 international caps and helped Portugal win Euro 2016.
West Ham are in FA Cup fourth-round action on Saturday when they visit League One leaders Wigan Athletic.
The Hammers are 11/5 to win the tie in 90 minutes and 11/1 to claim a 2-1 victory. West Ham can be backed at 12121/1 to win the FA Cup this season.
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