Manuel Pellegrini says he and West Ham currently doesn't know the severity of Michail Antonio's hamstring injury that forced him off during the Carabao Cup win against Newport County.
The winger pulled up after just seven minutes chasing an overhit pass from Aaron Cresswell, Antonio was also offside anyway, but went down immediately clutching his hamsting. He also motioned straight away that he needed to be substituted.
Felipe Anderson got an earlier than expected run out to replace one of West Ham's most in-form players.
Antonio was helped down the tunnel but two of the Hammers medical staff and was barely able to put any weight on his right leg as he was being taken to the medical room at Rodney Parade.
Manager Pellegrini was asked after the game if there was any update on the winger. The Chilean confirmed it was a hamstring injury but that there would need to be further assessment.
The boss said: "We will see tomorrow [Wednesday] but he has a hamstring injury.
"We will see how big it is but after the medical examination of course, we will know more."
If it is a hamstring tear then the usual minimum time on the sidelines is six weeks. If it is just a pull or a strain then it could be shorter so the Hammers are hoping it is good news after his is examined at Rush Green on Wednesday but the winger is almost certain to miss the home game against Norwich this weekend in the Premier League.
The Hammers went on to win the game 2-0 thanks to goals from Jack Wilshere, his first in claret and blue, and a tap in from Pablo Fornals midway through the second half in a professional performance against a known opposition with previous cup upset history.
