Manuel Lanzini has denied reports he will miss the entire 2018-19 season through injury and expects to return for West Ham early next year.
The Argentina international was ruled out of the World Cup after rupturing his anterior cruciate ligament in training earlier this month.
He underwent surgery with renowned Spanish orthopaedic surgeon Dr Ramon Cugat in Barcelona.
West Ham confirmed the surgery was a success and said the player would spend a couple of weeks recovering in Spain before heading back to London.
Lanzini, 25, refuted national newspaper claims there were problems with the operation, but would not put a specific timeframe on his return.
“The surgery went really well. Although I don’t want to set a date, I expect to be ready to play at the beginning of 2019. Thank you.”
West Ham’s new manager Manuel Pellegrini is continuing his search for midfield reinforcements, though.
The club have been frustrated in their pursuit of Fulham’s Tom Cairney and Argentine midfielder Javier Pastore, the latter joining Roma from PSG on Tuesday.
But Sky Sports News understands West Ham are interested in Arsenal’s Jack Wilshere, while they have also increased their offer for Lazio’s Felipe Anderson to £35m plus add-ons.