The striker, a boyhood Everton fan, took great delight in helping secure the title which took United ahead of Liverpool in the all-time list.
Cut above: Rooney put the picture on Twitter
Rooney scored from the penalty spot to earn United a 1-1 draw at Blackburn Rovers and claim the point needed to wrap up the title.
He said: 'Winning the Premier League is an incredible feeling and to get that 19th title to become the most successful English club is brilliant.
'Of course for me personally, being an Everton fan, it's even more special 19 times. It's a great feeling for the whole club, the team, the fans, everyone.'
Team-mate Michael Owenwas stunned by Rooney's new look.
He tweeted: 'None of us thought Wazza would send that picture! He is madder than we thought!!!'
Spot on: Wayne Rooney celebrates scoring a penalty at Blackburn
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