Arsenal have done exactly what they needed to do to make this tie interesting. After just seven minutes of play at the Emirates Stadium, the Gunners lead AC Milan 1-0, thanks to a goal by Laurent Koscielny on a corner kick. Koscielny scored a truly embarrassing own goal at the weekend against Liverpool and made a bad error in the first leg against Milan, so he'll be thrilled to atone for his errors somewhat.
The Gunners got off to a brilliant start and it wasn't terribly surprising when they scored. Alex Oxlade-Chamberlain delivered the ball to Koscielny, who lost his marker and headed into the back of the net. Arsenal are still very far behind and need to score four more times without conceding to force extra time, but this will not be a cakewalk for Milan. Arsenal have not yet conceded defeat.
For more on the two teams, head to Arsenal blog The Short Fuse, The Offside Arsenal and The Offside AC Milan.