Erling Haaland scored twice despite being a second-half substitute as Borussia Dortmund beat Koln 5-1 in the Bundesliga.
The 19-year-old - son of former Manchester City player Alf-Inge - had been linked with Manchester United before opting last month to swap Red Bull Salzburg for Dortmund.
Even though he netted a hat-trick on his debut, Haaland was named among the substitutes and was introduced just past the hour mark.
He grabbed his first goal 12 minutes later after pouncing on some loose defending to find the back of the net from close range in front of Dortmund's famous yellow wall.
As the game entered the closing stages, the Norwegian sensation struck again as he beat the offside trap and rounded the goalkeeper before finishing from a near impossible angle at the base line.
Last week's trio of goals made Haaland the seventh player in Bundesliga history to score a hat-trick on his debut and the first since Pierre-Emerick Aubameyang, who also did so for Dortmund and wearing the same number 17 shirt.
The brace tonight saw his total hit five goals in the space of a week and helped to move Dortmund up to third in the standings, level on points with Bayern Munich and four behind leaders RB Leipzig.
