Paul Pogba forced off with hamstring injury during Manchester United's game against Rostov and will miss Middesbrough clash

The 24-year-old appeared to have tweaked his hamstring during the incident on Thursday night.

And manager Jose Mourinho admitted he could be out for an extended period: 'I don't know for sure, but for sure, no Middlesbrough and no national team.'

Defender Daley Blind also had to leave the pitch with an injury within five minutes of Pogba's departure. 

Manager Jose Mourinho has previously referred to Fellaini as Pogba's 'natural replacement'.

He wrote in November 2016: 'Unfortunately tonight, we are without Paul Pogba and his natural replacement, Marouane Fellaini, who both picked up bookings on Sunday, but I have the players who can do the job despite those problems.'