Ross Barkley is set to miss Chelsea’s trip to Watford after suffering an injury that could prompt further questions over the club’s record of hamstring problems under head coach Antonio Conte.

It is feared Barkley may have suffered a hamstring injury in training this week, although the exact nature and severity of the 24-year-old’s problem has not been fully established.

There is currently no suggestion that Barkley’s injury is connected to the severe hamstring injury that prevented him from making his first appearance of the season until Jan 24 after joining Chelsea for £15 million from Everton.

But Barkley is being assessed by Chelsea medics and if it is confirmed he suffered a hamstring injury, then he will be the eighth victim of the campaign.

Andreas Christensen became the seventh Chelsea player to suffer a hamstring injury during the shock midweek defeat to Bournemouth, following on from Alvaro Morata, Victor Moses, N’Golo Kante, Gary Cahill, Cesc Fabregas and Willian.