Brown was handed his first start in the Barclays Under-21 Premier League this season, and the front man did not disappoint.
The striker joined the Club from Arsenal in the summer and scored twice in the 5-3 defeat.
Haycock told whufc.com: "He's a young 17-year-old and playing against his ex-club he was keen to play and I think he handled that well, because it's often difficult playing against the club where you've been since you were a young schoolboy.
"He wants to learn, you can see he's a goalscorer and there are parts of his game which we'll work on on the training pitch. He was unlucky not to get a hat-trick with the header that came off the post as well as a few other little chances.
"All in all I'm looking at the performance as a whole and I always take the positives. I thought the second goal was a very good goal and we should have played like that more."