Julian Weigl proved baffled after his first goal for Borussia Dortmund proved decisive in the 2-1 Champions League Group F win over Sporting Lisbon.
Pierre-Emerick Aubameyang's third goal of the competition got Thomas Tuchel's side up and running and sparked a superb first-half display at the Estadio Jose Alvalade.
The result was crowned by a spectacular and unexpected strike from Weigl, who revealed that it was not a move that he had practiced before.
"I don't even know what I did," said the Germany midfielder, who had never previously found the net at senior level before he rifled home from 25 yards in the 43rd minute.
"It happened instinctively. I'm just happy it finally worked."
Substitute Bruno Cesar hauled Sporting back into the contest and set up a nervy finish for Tuchel, who was forced to substitute three of his starting back four by the final whistle.
Nevertheless, the Dortmund boss was still keen to have fun at Weigl's expense post-match.
"I only remember one other goal [from Weigl]," he said. "It happened in the final training session before the PAOK match [in last season's Europa League]."
"It was so special we have it on video."
Dortmund came into the match having picked up a solitary Bundesliga point from their games either side of the international break but displayed steel to collect all three points at Sporting.
And Tuchel was impressed by the collective resilience on show as Marc Bartra, Matthias Ginter and Felix Passlack all made way during the latter stages.
"Our back four after the 70th minute was unique," he continued. "We were incredibly young and inexperienced. We played with such a matter of course during the first half, so strong and so effective.
"After half-time we had to suffer for 15 minutes because we completely lost the thread. In the phase where we had the game completely reassured, we made two simple mistakes to give a goal away.
"My men wanted the win and gave more under the circumstances. Throughout the second half we had a bit of luck but it was not undeserved for us to win here."