Photo: Muhammad Ali MY FIRST SELFIE ... Is the Greatest!

He's only been on Instagram for 3 weeks, but Muhammad Ali has already posted his very first selfie. The 72-year-old champ was decked out in Louisville shirt to cheer on the Cardinals as they took on the Kentucky Wildcats this weekend. 

Ali wrote, "#Louisville Game Day! Go Cards!"

It's the first time Ali has posted a new photo on any social media platform since he joined Twitter in 2010. 

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