The former UFC bantamweight champion stepped up to featherweight at the historic pay-per-view card.
And he dominated striking specialist Kattar over three rounds with an expert display of grappling.
But the wrestling-heavy approach did not please the paying crowd inside the T-Mobile Arena in Las Vegas.
They refused to hold back by mercilessly booing Sterling and even counted down the final ten seconds of the third and final round.
Much to their relief, the bout came to a close and Sterling, 34, got his hand raised on the scorecards.
But there was no post-fight interview for the New York-born star.
Although fans on social media made their feelings known as one said: “I want a refund on the 15+ minutes I wasted on the Sterling fight.”
Another added: “Bought the PPV, just watched the Aljamain Sterling fight, so disappointed that I feel a refund would be necessary…”
One fumed: “Bro needs to be fined 300k for that fight.”
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Another raged: “Might need a refund after that Aljo fight.”
But another argued in his defence: “If that dominant performance is boring to you, this isn’t the sport for you.
“Just stick to the bar fights on a Saturday.”