Alejandro Garnacho took advantage of a rare Manchester City mistake to give Manchester United the lead in the FA Cup final. 

Pep Guardiola's men dominated much of the possession and limited United to a few efforts in a cagey first 30 minutes. 

Diogo Dalot played a long towards the edge of City's box and Josko Gvardiol shrugged off  Garnacho and attempted to head it back to Stefan Ortega, who had already come off his line. 

The Argentine winger got in behind and guided the ball into an empty net to put Erik ten Hag's men a goal up. 

And fans were quick to react on social media, as some blamed Ortega for the mix-up which lead to the goal. 

One said: 'People will point the finger at Gvardiol, but there’s absolutely no reason Ortega should be coming out there. Like, why would you do that? Would’ve been an easy header back had he just stood his ground.' 

Another wrote: 'Where the hell is the communication between Ortega and Gvardiol'. 

'Wtf is this goal I thought I was watching Saudi league', said a third fan said. 

United went on to double their lead in the 39th minute through Kobbie Mainoo. 

The midfielder finished from close-range from a superb no-look pass by Bruno Fernandes.