Hakan Calhanoglu's long-range striker had given Milan a 1-0 lead on the night going into half-time, but the England worldwide striker went down in the opposition's area under minimal contact from Swiss defender Ricardo Rodriguez to earn a spot-kick before the break - before dispatching the opportunity to bring the hosts level.
"We played well and it's not easy to do that here". The Italian players were not happy.
"(Welbeck's) a striker, he has to do what he does", Milan boss Gennaro Gattuso said. "I'm not going to judge".
Atletico players celebrate after scoring their side's second goal during the Europa League, round of 16 second leg soccer match between Lokomotiv Moscow and Atletico Madrid, in Moscow, Russia, Thursday, March 15, 2018.
Earlier on Thursday, Fernando Torres scored twice as Atletico Madrid romped to a 5-1 Europa League thrashing of Lokomotiv Moscow in Russian Federation to complete a resounding victory.
However, Danny Welbeck's controversial penalty got the Gunners back on level terms.
Welbeck's theatrics were condemned by pundits, while Swedish referee Jonas Eriksson was slammed for being tricked by the play-acting.
What do you think of the draw and will you be going? There is a lot of fair play in England.
"I don't want any alibi".
"I knew what I had to do", he said.
Arsenal'sDanny Welbeck scores their first goal from the penalty spot.
The Gunners went into the game with a healthy 2-0 advantage following an impressive win at the San Siro a week ago.
The problem is that it will take the gloss of Arsenal's win and, even though they are into the quarter finals, former players, pundits and TV experts were queuing up to condemn it. Gary Lineker called it a "blatant dive", Jermaine Jens called it "cheating" and Alan Shearer insisted the referee was "conned". "In the same way (goalkeeper Gianluigi) Donnarumma made a mistake, as you can, a referee can make a mistake as well". We have to wait and see who we get.
Victory ensured Arsenal reached a European quarter-final for the first time since 2010, while they werejoined in the quarter-finals by Atletico, CSKA Moscow, Lazio, RB Leipzig, Marseille, RB Salzburg and Sporting Lisbon.
"I hope so. When we looked at the draw before, AC Milan was probably not one of the teams we fancied but we showed we can play against the top teams in Europe".
Astronaut's DNA changed by time in space
The altered genes are related to Scott Kelly's immune system, DNA fix and bone formation networks, among other bodily functions. Bailey said her research, and nine other studies, aren't finalized yet and should be released from NASA later this year.
Met Office issues yellow weather warning for snow
The Telegraph was also told by the Met Office that there could be between two and five centimetres of snow in some areas. Drivers have been warned by the RAC that they should ensure they are ready for potentially unsafe road conditions.
Assassination of Rights Defender, Driver
As Franco was leaving the site, a auto pulled up to the side of her own vehicle and fired nine shots into it. Investigators reportedly suspect that Franco, 38, was the victim of a targeted assassination.
OPEC acknowledges supply cuts didn't work
Restraint shown by United States producers supports Goldman Sachs Group Inc's bullish oil view, the bank said in a report. Natural gas prices are being supported by this nasty late winter, but if you look at the calendar it will not last.