The Argentina international made his return from a foot operation off the bench against Tottenham Hotspur in the Premier League in the middle of January before starting three straight games against Newport County, Wolverhampton Wanderers and West Ham United.
Martinez was forced off in the 71st minute of Sunday's clash with West Ham, though, having suffered a knee injury, and it was revealed on Monday that he is now facing eight weeks on the sidelines.
Ten Hag has opened up on the «setback», detailing the importance of the defender to the team.
«Yeah, it is a setback of course. Licha was just returning. You see his contribution to the team when he is playing so he brings, apart from his technical skills, also a mentality in the team,» Ten Hag told reporters during his press conference on Thursday afternoon.
«It is a big setback for Licha. He is very disappointed, but he is a fighter and he will back, he will be back stronger. We think he will still be back by the end of the season.
»There are games to play so as a squad we have to replace him. We have very good players in that position who will play there and perform there and as a squad we have to deal with it."
Ten Hag also played down claims that Martinez's desire to initially play on after suffering the injury caused it to become a bigger problem.
«I don't think so but Lisandro, it was his decision, and he was comfortable to be back on the pitch. But after he tried and then he stopped in the next attack,» he said.
«In some situations it is clear and obvious. There is always a grey area and it is very
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