By Harry Sykes

Aleksandar Mitrovic could be facing a lengthy spell on the sidelines after being stretchered off during the first half of Newcastle’s FA Cup clash against Birmingham on Saturday.

The Serbia international dropped to the turf wincing in pain immediately after Daryl Murphy had given Rafael Benitez’s side a fifth-minute lead in the St James’ Park fixture.

Mitrovic appeared to have suffered a suspected broken leg as he was stretchered off with his leg in a brace and was taking oxygen through a mask.

Air braces are usually applied when there is a suspected break to the bone, with the strong possibility that Mitrovic has sustained serious damage.

This could rule the 22-year-old out for up months in what would be a shattering blow to Newcastle as they chase promotion back to the Premier League.

Mitrovic has had to play second fiddle to the Championship’s leading scorer Dwight Gayle this season but he is still regarded by Benitez as a key man and the manager has repeatedly said the Serbian will not be allowed to leave Newcastle this month.

Mitrovic has scored five goals and supplied two assists from 16 matches this season, with many of his appearances coming as a substitute.

He was restored to the Newcastle starting XI on Saturday as Benitez made eight changes to the side that lost to Blackburn in the league on Monday.

Football Insider verdict

It will be a huge blow to Newcastle’s promotion challenge if the fans’ worst fears are realised and scans show that Mitrovic has broken a bone and will be sidelined for months. The Serbian has been second choice to Gayle this season but he still represents proven back-up in the striker position and has a knack of getting goals when they’re most needed. Benitez will be nervously awaiting medical confirmation on Mitrovic’s injury before deciding whether he needs to buy a new striker this month.

In other Newcastle team news, the Magpies are closing in on the signings of three Everton players.