You couldn’t blame Arsenal fans for fearing the worst ahead of the FA Cup final clash with Chelsea.Chelsea finished 18 points clear of the Gunners in the Premier League and were heavy favourites for the cup final at Wembley.Arsenal’s case certainly wasn't helped by the fact they were without defenders Laurent Koscielny and Gabriel - meaning Per Mertesacker started his first game of the season.However, Arsene Wenger’s side tore up the script inside the opening few minutes.The north Londoners started strongly, putting the champions under pressure.And they got their reward after just four minutes.Alexis Sanchez charged down N’Golo Kante and ran onto the ball to finish past Thibaut Courtois.But there was confusion.Aaron Ramsey was standing in an offside position when Sanchez closed down the ball and made a movement towards it. That prompted the linesman to stick up his flag as Sanchez finished.However, after referee Anthony Taylor consulted with his assistant, he allowed the goal because he deemed Ramsey not to be interfering.Confusing? Yes.Controversial? YesThe right decision? We'll let you decide:

Watch: Sanchez's goal

But was it handball?

But was it handball by Sanchez as Kante tried to clear the ball?

That's certainly what it looked like and plenty of people on Twitter thought so. Check out the reaction:

Of course, Arsenal are hoping to win the FA Cup in a bid to save their season. After they finished fifth in the league - missing out of Champions League qualification - an FA Cup triumph would be the only way to save their campaign.

As for Chelsea, an FA Cup win would represent the perfect season for them having already won the Premier League. A double in Antonio Conte’s first season would be a rather remarkable achievement.