Arsenal started the north London derby strongly against Tottenham, but it was Spurs who struck first after a series of defensive errors from the Gunners.
Christian Eriksen's future at Tottenham remains uncertain, but Mauricio Pochettino recalled the Danish playmaker to his starting XI for Sunday's must-win derby at the Emirates.
Spurs badly missed Eriksen's creativity as they fell to a shock 1-0 home defeat against Newcastle last weekend, but the midfielder repaid Pochettino's faith 10 minutes into the north London derby.
Tottenham went in front after only 10 minutes with a goal that left goalkeeper Bernd Leno a touch red-faced.
The German stopper could only push Erik Lamela's low strike into the path of the advancing Eriksen, who gratefully tapped home a simple opener.
🤭 OH NO LENO!
A nightmare for the @Arsenal keeper allows Eriksen to tap in after a slick @SpursOfficial counter-attack 👌
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But Leno was not solely to blame with Sokratis Papastathopoulos caught out of position from the initial flick-on from Harry Kane, with the rest of Arsenal's defence also caught flat-footed as Heung-min Son teed up Lamela for the initial effort.
Scroll through the gallery below for all the best photos from the Emirates.
Additional reporting by the Press Association.