Haaland joined Dortmund from Austrian side Red Bull Salzburg in the winter transfer window and has quickly hit the ground running.
The Norway international stole the show again in Dortmund’s 5-1 win over FC Koln on Friday night.
Haaland came on as a substitute on the 65th minute mark to score twice in 10 minutes for Die Borussen.
The 19-year-old has now scored five goals in two matches as a substitute in just 57 minutes.
Witsel is surprised by Haaland’s bright start to his career at the Signal Iduna and insists he hopes he keeps scoring.
“It’s crazy,” Witsel told Bundesliga.com, dazed by Haaland’s performances.
“To come on in the first games and score goals, that has not happened since Aubameyang.”
“We needed a stronger striker, and the club did really good on this one. We’re all happy he’s here.”
“For his age, he’s really strong. He’s tall, he’s big, he has a lot of quality. He can keep the ball.”
“For a big guy, he’s quite technical and in front of goal he’s a killer. I hope he’ll keep scoring like this for the next game.”