Alexis Sanchez’s deflected free-kick looked to have handed Arsenal a 1-0 win until the closing minutes of the game.
Mike Dean awarded the Baggies a controversial penalty after adjudging Calum Chambers to have handled the ball in the box.
Jay Rodriguez duly slotted the spot-kick past Petr Cech to earn his side a share of the spoils.
Arsenal players swiftly crowded Dean at the final whistle to argue why he decided to give a penalty.
And social media was awash with people asking the same question.
Arsenal fan and TV presenter Piers Morgan joked Dean’s decision put him on a par with North Korean leader Kim Jong Un.
He said: “Breaking: Mike Dean sneaks in to wi the ‘Worst Human Being on Planet Earth in 2017’ award right at the year’s death. Kim Jong Un must be thrilled. #wbavafc”
Comedian Jack Whitehall claimed Dean wanted to make 2017 all about him.
“Mike Dean taking a last gasp opportunity to make 2017 all about him,” he wrote.
While another Gunners supporter stated his disbelief that Dean is still a Premier League referee.
“How is Mike Dean still a Premier League official?” They said.