Borussia Dortmund needed a spark on Wednesday. In its first leg of the Champions League round of 16 against Benfica, it had utterly dominated the Portuguese in Lisbon but somehow lost 1-0.

It got that spark from 18-year-old American Christian Pulisic, whose assist and goal were all Die Borussen needed to take the tie on aggregate. Pierre-Emerick Aubameyang would get two more anyway, completing his hat trick, for a comprehensive 4-0 win that sees the American and his peers into the quarterfinals with a 4-1 aggregate score.

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In the fourth minute, Pulisic deftly headed on a corner at the near post. Aubameyang then headed it in at the far post to bring Dortmund level with Benfica at 1-1 on aggregate.

Before halftime, Pulisic attempted a long header from the edge of the box from a misplaced cross, but he forgivably couldn’t get enough power on it.

In the 59th minute, however, he would score his first Champions League goal in 11 appearances and his sixth professional goal overall.

Lukasz Piszczek played a shrewd through ball to the attacking midfielder that he disguised well. The Pennsylvanian did well to stay onside, pivoted his body around the ball and chipped his finish over Ederson first-time for a sublime goal.

That made it two games in a row that Pulisic tallied both a goal and an assist, after he did the same in Dortmund’s 6-2 destruction of Bayer Leverkusen on Saturday, leading to Leverkusen’s firing of its manager Roger Schmidt.

Pulisic’s rich vein of form – some called his game against Benfica one the best of his young career, and certainly his best in continental play – is potentially well-timed. On March 24 and 28, the United States men’s national team plays crucial World Cup qualifiers when such flashes of precocious brilliance will be very welcome.

Leander Schaerlaeckens is a soccer columnist for Yahoo Sports. Follow him on Twitter @LeanderAlphabet.