Those are the views of former Sky Sports pundit Richard Keys, who was impressed with how the Arsenal star kept Chelsea at bay on Saturday.
The Gunners ended a testing season on a high with a 2-1 win at Wembley, with Alexis Sanchez and Aaron Ramsey putting Antonio Conte's side to the sword.
Mertesacker was a rock at the back, nullifying the threat of Diego Costa in his first start in over a year.
The former Germany international was paired alongside Rob Holding with Laurent Koscielny and Gabriel sidelined through suspension and injury respectively.
And Keys was left so impressed by the veteran's display that he believes he deserves the label of the Arsenal's player of the season.
Arsene Wenger lifts FA Cup as Arsenal players celebrate Sat, May 27, 2017
Arsene Wenger was the centre of attention during the wild Arsenal celebrations
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Arsenal celebrate winning the FA Cup against Chelsea
Per Mertesacker should get Arsenal's Player of the Year award, according to Richard Keys
"Never mind man of the match, Per Mertesacker should be named as a Arsenal's player of the year. He was awesome," he wrote on his blog.
"If the win transformed Arsenal's season – and it did – then Mertesacker had more influence on that season in that 90 minutes than anybody else.
Whether or not the FA Cup triumph transformed Arsenal's season is debatable.
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Per Mertesacker helped Arsenal win the FA Cup at Chelsea's expense on Saturday
Though the Gunners joined Chelsea and Manchester United in becoming the only two teams to win a trophy, they also failed to secure Champions League football for next season for the first time in 21 years.
And they also finished behind rivals Tottenham, who sat above their rivals in the final league table for the first time since 1995.
As for their player of the year award, then Sanchez is surely a shoe-in for the prize.
The Chile international scored 30 goals from 51 games, registering nine assists along the way.