Pernille Harder’s hat-trick ensured Arsenal’s return to the Women’s Champions League ended in defeat in an end-to-end encounter against Bayern Munich in Germany.
The former Chelsea forward, who had failed to score in her previous five European games, met Carolin Simon’s corner to head her side into a 3-2 lead.
This came eight minutes after Laia Codina had powered in a header from Katie McCabe’s corner to level the tie at 2-2.
Denmark international Harder cemented the points for the hosts with another header in the 78th minute, before completing her hat-trick four minutes from time after goalkeeper Manuela Zinsberger spilled her initial save.
The Gunners started the game on the front foot with Mariona Caldentey giving them the lead after half an hour after expertly volleying McCabe’s cross beyond keeper Maria Grohs.
After falling behind, German champions Bayern started to apply pressure on the Arsenal backline and found the leveller 13 minutes later thanks to an unstoppable header from Glodis Viggosdottir.
The Bayern Munich captain rose highest in the box to expertly loop a header over Manuela Zinsberger after a pinpoint diagonal ball from England midfielder Georgia Stanway.
Alexander Straus’ side were in the ascendency after the equaliser and came close to scoring before Lohmann drilled her right-footed strike into the bottom corner to make it 2-1.
Next up for Jonas Eidevall’s side in Group C is the visit of Norway’s Valerenga on Wednesday, October 16.
Tough start to season continues for Arsenal
After three games in the Women’s Super League (WSL), Arsenal sit sixth having won once and drawn twice.
The Gunners flew to Germany under pressure to perform after the goalless draw with bottom side Everton on Sunday left supporters wondering whether they could keep up with Chelsea and Manchester City in the title race.
Arsenal started the match against Bayern on the front foot and their attacking efforts produced the opening goal on the half-hour mark.
Eidevall’s side deserved the lead but showed their frailties when the hosts started to push for the equaliser, which came shortly after Caldentey’s opener.
The start of the second half will frustrate the Gunners, who could have kept it tight and fought their way to a point, or even threatened on the counter-attack late on.
Instead, Bayern attacked at will and took the lead early in the second half before Codina dragged Arsenal level.
A point for the Gunners seemed to be on the cards, but Harder’s 13-minute hat-trick quickly extinguished the visitors’ hopes.
Things do not get any easier for Arsenal as they host WSL champions Chelsea on Saturday (13:45 BST).