Manchester United have a defensive injury crisis at present and centre-back is at the heart of the problems. Erik ten Hag announced at his midweek press conference that Raphael Varane, Harry Maguire and Jonny Evans are back in training. It was a welcome relief after injuries to Victor Lindelof and Lisandro Martinez, again. Getting to the end of the season intact will be an achievement. Next season, this position requires an overhaul. Four of the five centre-backs will be over 30 next season, with the one exception, Martinez, a player who cannot stay fit. READ MORE: Fabrizio Romano names the fo…