The pair worked together at RB Leipzig.
Hasenhuttl smiled: "I knew the moment would come that he scored his first goal in the Premier League. I hoped it would not be against us.
"When you give him space, it's hard to defend against him. The first goal we made it too easy for him.
"It's tough to defend against him. When you are not tight on Timo and Kai Havertz they will kill you.
"But I am really happy that Timo is in England and playing in the Premier League. He's fantastic for the fans, but it's good we took a point as otherwise I wouldn't be so happy for him."