The Gunners were coasting to an easy win as Mesut Ozil made it 4-0 with the simplest of finishes inside the box.
But Leno could not toast his debut with a clean sheet as Vorskla rallied and halved the arrears - Volodymyr Chesnakov pulling a goal back before Vyacheslav Sharpar scored with the final kick of the evening. He didn't say the Premier League is Petr's competition and the Europa League is mine.
The first of those titles came in 2013-14 as Emery's Sevilla topped Benfica in the finale, while the club followed that trophy up with another the next year by defeating Ukrainian club Dnipro Dnipropetrovsk.
Leno's performance gave every indication that he is indeed more suited to Arsenal's new style of play, and it was put to Emery that the 26-year-old might keep his place for Everton's visit on Sunday.
The road ahead will nearly certainly get more hard for the Gunners, as Vorskla entered Thursday's match without a win in Europa League play, having drawn two and lost five of their seven total games in the competition in club history.
'I have a lot of confidence in him, but also the other strikers like Danny Welbeck and Alexandre Lacazette. "My first idea is to find the best performance each match, and every competition for us is very important", he said. "I will work every day hard to play more games".
Arsenal coach Unai Emery has promised Bernd Leno will get more chances to impress after the goalkeeper aired his frustrations over a lack of playing time. "And today I think was a good opportunity for not conceding goals, but I think the last 20 minutes, we need to be better on this competitive aspect". "We want to do better in this minute", he told BT Sport.
Aubameyang is expected to start when Arsenal host Everton at the Emirates on Sunday and the club will be hoping to see him add to his tally of goals. I want to continue to be competitive in each match.