Arsenal missed out on the chance to go top of the Premier League as they were held by Tottenham in a closely contested north London derby.
Kevin Wimmer headed Mesut Ozil's free-kick into his own net under pressure from Laurent Koscielny and Alexis Sanchez, who appeared to be offside.
Koscielny was harshly penalised for a foul on Mousa Dembele in the box and Harry Kane converted the spot-kick on his Spurs return after seven weeks out injured.
Kane was denied a second by a superb Nacho Monreal block before Christian Eriksen's cross from a free-kick struck the post.