By Chris Harris at Emirates Stadium
We still have work to do to reach the knockout stage of the Europa League after slipping to defeat against Frankfurt.
Pierre-Emerick Aubameyang scored his 10th goal of the season to give us the lead, meeting Gabriel Martinelli's low cross with a first-time shot that pinballed off the goalkeeper's trailing foot and bounced off the crossbar, onto the goal line and up into the roof of the net.
It was an unusual end to a flowing move that was started by Bukayo Saka, and it was no more than we deserved after making most of the running against the German side.
Joe Willock went close with a header and Martinelli was denied twice in a minute - including a header that was cleared off the line.
We looked pretty comfortable at the break but a fizzing left-foot strike from Daichi Kamada changed the game in the second half.
The goal lifted Frankfurt, deflated us, and Kamada added a second with another good finish after we could only half-clear a corner.
Saka had a penalty claim turned down as we chased an equaliser, but Frankfurt held on for the win.
HOW IT HAPPENED
THREE THINGS WE NOTICED
WHAT IT MEANS
Granit Xhaka was back in the team for the first time since he was substituted against Crystal Palace on October 27.
The midfielder was one of six changes from our draw against Southampton. Also coming into the side: Emi Martinez, Shkodran Mustafi, Willock, Martinelli and Saka.
Another away trip beckons - we're at Norwich City in the Premier League on Sunday.
Our next home game is also in the league, against Brighton and Hove Albion next Thursday.
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