Marko Arnautovic has confirmed in an Instagram update that he is set for a spell on the sidelines.

The West Ham striker posted a picture of himself on an Instagram story, shown by the club’s official Twitter account via a screenshot, where he confirms his injury extent.

“Out for a while”

Arnautovic has been struggling with knocks all season and he has not been at full tilt.

Against Cardiff, he was substituted in the first half, clutching his hamstring.

The Austrian striker then gave the following update in a caption on his Instagram: “Thank [you] so much for all your messages. I will be out for a while. But I will do everything to come back strong and quick.”

How long is he out?

Marko Arnautovic limped off against Cardiff City. (Photo by Arfa Griffiths/West Ham United via Getty Images)

The official diagnosis of Arnautovic’s injury has not been announced yet by any official source.

But The London Evening Standard believes that the 29-year-old will miss the whole of December and return in 2019.

Below are what West Ham fans had to say after their talisman was ruled out for a “while”.