The 19-year-old Norwegian striker was not fit enough to play a full match.
The Borussia Dortmund coach Lucien Favre revealed that Haaland barely trained during the festive season due to a niggling knee problem.
Nonetheless, the young attacker needed only 180 seconds into his debut to hit the ground running at Signal Iduna Park.
When entering the fray in the 56th minute, Dortmund was trailing Augsburg 3-1 goals.
Augsburg took the lead through their striker Florian Niederlechner following poor defending by Dortmund defenders.
Marco Richter scorcher meant the players went for the halftime break with Augsburg leading by two goals.
Germany winger Julian Brandt halved the deficit when his shot cannoned in off the crossbar.
However, their hopes of a comeback were momentarily dampened when Niederlechner tapped in for his second of the night.
Haaland then entered the fray replacing Polish defender Lukasz Piszczek, a move that reinvigorated Dortmund’s attack.
England’s winger Jadon Sancho took up from where Haaland left it to equalize, he converted from a tight angle after going round the Augsburg goalkeeper.
Haaland then completed his 20 minute hattrick minutes thereafter to show why Dortmund parted with 30 million Euros to secure his services.
He tapped into an empty net for his second following good work from Thorgan Hazard.
His team captain, who endured an awful afternoon in front of goal, slid him through to complete his hattrick.
Michael Zorc, the Dortmund Sporting Director, said:
“He is still young and we would advise against expecting too much, but he brings us a lot of strength and has an incredible mentality.”
Favre pointed out that:
“He moves well between the lines, gives us more attacking possibilities and at 19 years old, he has a huge potential for improvement, that’s the most important thing.”