Ten Hag's men led 2-0 at the break, through Jadon Sancho and an own-goal by Matty Cash, but Leon Bailey pulled one back before Chambers headed in from a corner. Speaking to club media after the final whistle, the boss was clear on how things can be improved.
With friendlies to come against Atletico Madrid and Rayo Vallecano next weekend, both live on the United App, there will be more fine tuning before the big Premier League kick-off, with the Reds entertaining Brighton & Hove Albion on 7 Auguest.
"First half was a decent performance, 2-0 up, but, the second half, we came back out of the dressing room, we had control of the game and we gave it away," explained Ten Hag.