Chris Smalling is believed to be out for up to four weeks after suffering a broken toe in training with Manchester United, meaning he will miss his side's tie with Arsenal next Saturday.

Smalling was not called up to Gareth Southgate's England squad having missed United's 3-1 win against Swansea City in the Premier League, alongside left-back Luke Shaw. Manchester United have not confirmed Smalling's injury, nor how long the Englishman could be out for.

Smalling reportedly ruled out with broken toe

This is one of numerous defensive injuries for Jose Mourinho to deal with, and comes in the wake of the Portuguese manager supposedly ordering a review into the medical set-up at the club. Eric Bailly suffered knee ligament damage in the humiliating 4-0 loss against Chelsea while Shaw has struggled with injury and fitness in recent weeks. Antonio Valencia, having cemented his position as first choice right-back for Mourinho, underwent surgery on a fractured arm and will be out for at least another three weeks.

Smalling had already been out for four consecutive United games due to a minor ankle injury, according to Mourinho. His absence will hit hard, even though he hadn't been starting. Mourinho may look to promote under-23s captain Axel Tuanzebe to the first-team to fill the gap left by Smalling.

Tuanzebe could be promoted to fill gap

Tuanzebe is a composed centre-back who has previously drawn individual praise from Mourinho. During pre-season, having played in United's first game of the Mourinho era, against Wigan Athletic , Tuanzebe was picked out by Mourinho. Since then, his name has been mentioned by the United boss in multiple press conferences.

Ro-Shaun Williams is another potential candidate to be promoted, having spoken to VAVEL UK on Thursday after being in action for England's under-19s side. Williams told this website that training with the first team has "been a good experience," and he is "just working hard with the under-23s." Williams is hoping to "keep pushing and try to show the manager what I've got and then hopefully get into the first team."

Williams has seen the example of Marcus Rashford and says that "obviously it gives you confidence." He continued to say that "him getting into the first team just shows that you just need one chance, one opportunity and you’ve got to take it.”

Daley Blind and Marcos Rojo are almost undoubtedly set to be United's centre-back pairing at home to Arsenal on Saturday, November 23rd.