The Chelsea starlet completed a move to the Bundesliga side earlier this month and has wasted no time in making his mark.
Lining up at left-back for Dortmund, the Dutchman recorded the perfect assist as he dispossessed his opponent deep in his own half before breaking through.
Surging up the field, Maatsen lifted his head and played a stunning diagonal pass to release Donyell Malen, who was left with the simple task of slotting past the goalkeeper.
The 21-year-old, who boasts a reported £35million release clause in his Chelsea contract, is renowned among his admirers for his vision and ability to pick out a pass, something that has already been noticed by a number of Dortmund fans.
One said: "£35million seem low as buyout clause for Maatsen. Holy s***."
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Another commented: "Maatsen is already the new Marcelo for many BVB fans."
Meanwhile a third fan remarked: "It doesn't matter if the clause for Maatsen is €35 or €40million, they HAVE to pay it. He's the best player on this team and it has been just two matches."
Meanwhile Chelsea's fans were not shocked to see just how well he was performing.
"Ian Maatsen flourishing with Borussia Dortmund. Absolutely no one is surprised," said one fan.
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Another messaged: "Ian Maatsen should have got more chances to show what he can do at left-back."
This fan then posted: "Maatsen has turned into prime Roberto Carlos since being discarded and failed by Poch. Imagine my shock."
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Dortmund do not have an option to turn Maatsen's temporary switch into a permanent stay, but can - like any club - activate his buyout clause.
And if he can replicate this sort of performance, that sort of fee could be an absolute bargain.