United were woeful all round in losing 1-0 at St. James' Park – in a game which, despite the narrow scoreline, the hosts utterly dominated, racking up 22 shots to the visitors' eight.
But Ten Hag appeared particularly unimpressed with Martial's performance, laying into the French forward before half-time.
Martial was ultimately substituted just after the hour mark, and Ten Hag has stood firmly by his own actions, stressing that they were for the good of the side as a whole.
Speaking at full-time, the Dutchman explained: "It's not about Anthony Martial; it's about the team. I try to energise the team and try to get a reaction from the team in this moment. As you see, we had a tough period and when you're coaching, you are a little more aggressive, so that's normal."
United certainly are enduring a difficult spell right now: they've won only three out of seven games since the start of November, going out of the Carabao Cup to Newcastle, and finding themselves on the brink of Champions League elimination after twice throwing away a two-goal lead at Galatasaray in midweek.
There is a sense that the pressure is really building on Ten Hag, who has been in charge at Old Trafford for a little under 18 months now.
He'll be demanding a big reaction from his players when they return to action on Wednesday night at home to Chelsea in the Premier League.
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