Referee Anthony Taylor consulted with the linesman before awarding the goal to Arsenal.
Arsenal even had the luxury of a man advantage from the 68th minute when Victor Moses received a second yellow card for diving.
The Arsenal manager watched his side win 2-1 at Wembley against the heavily fancied Chelsea at Wembley.
But Arsenal dispelled all doubts three minutes later when substitute Olivier Giroud cut back for Ramsey to restore their lead with a header into a gaping goal.More news: Trump Vows to 'Get to the Bottom' of the Leaks
They were favourites to win the FA Cup for an eighth time but they were second best on the day to Arsene Wenger's Arsenal, who lifted the trophy for a record 13th time after finishing fifth in the league.
Chelsea team manager Antonio Conte stands on the sideline during the English FA Cup final soccer match between Arsenal and Chelsea at Wembley stadium in London, Saturday, May 27, 2017. Every player performed 120 percent or 130 percent every single game.
Arsene Wenger stuck with David Ospina in goal for the final, with club captain Per Mertesacker making his first start of the season and Alex Oxlade-Chamberlain deployed in an unfamiliar left wing-back role.
"I hope he stays here, he's been fantastic for me and fantastic for these players".
Chapeau to Arsène Wenger, the first manager to win the FA Cup 7 times. "It was right to celebrate, to enjoy this (league) win", he said.More news: Donald Trump's first foreign tour: his most awkward moments
So, if we look at it logically, Wenger has done well in winning Arsenal yet another trophy in a game that hardly anyone gave us a chance in.
'It wasn't easy to lose, but it was still a good season, ' said the Spain global.
Moses' sending off proved another key moment for Conte, but the former Juventus boss was mostly frustrated by his side's failure to maintain parity for a measly 38 seconds.
"Overall I just want to do well for this club and apart from that it's down to the board members to decide whether I'm the right man to take this club further".More news: Kislyak: Kushner Wanted Link to Kremlin
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