Arsenal fought to a draw against Atletico Madrid this evening to give themselves a narrow advantage in their Champions League semi-final tie ahead of next week’s second leg. A first-half penalty from Viktor Gyokeres was cancelled out by Julian Alvarez ’s second-half spot-kick, and the game ended level after a series of saves from David Raya, a superb block from Gabriel and a contentious decision to overturn a penalty after a challenge on Eberechi Eze in the box. While Atletico threatened at times after their equaliser, Arsenal controlled large periods of the game at the Metropolitano, and the result means the Gunners go into next week’s second leg as slight favourites as they look to book a place in a first Champions League final since 2006. Here’s what we learned as the Gunners earned a hard-fought draw at the Metropolitano.…