After victory over Fulham, Ten Hag was asked about summer market plans.
He said: "The club knows that a position in the top four and the fight for trophies in this tough league requires investment in new players. If you don't do that, you end up stagnating because other teams are investing.
"We saw it in the winter transfer window. All the clubs around us invested. We didn't, but we managed anyway, and that's why I'm very happy and proud of my players."