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Manny Pacquiao ended his brief and unofficial retirement when he took down Jessie Vargas by unanimous decision Nov. 5, and he's reportedly set to re-enter the ring with a 60th career win in his sights.

According to ESPN.com's Dan Rafael, Top Rank promoter Bob Arum said Pacquiao will fight Australian Jeff Horn (16-0-1) on April 22. The site of the fight has yet to be determined, but Arum told Rafael it will likely take place in Australia or the United Arab Emirates.

There was some buzz that Pacquiao's next fight would pit him against Floyd Mayweather Jr. in a rematch of their May 2015 clash—in November, Arum estimated there was a "75 percent" chance the two would fight again, per Rafael—but those plans have yet to come to fruition.

Instead, Pacquiao will square off against the undefeated Horn, who has won 11 of his 16 fights via knockout.

The 28-year-old will be seeking his biggest win to date when he squares off against the WBO welterweight champion. And if he pulls off an upset, there are indications Arum could have big plans for the Aussie sensation.

According to the Australian Associated Press (via the Guardian), "Arum has been enamoured with the former schoolteacher and 2012 Olympian ever since and believes he has the ability and image to carve out a U.S. fanbase."

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But when it comes to selling April's fight, Arum and Co. figure to have a tall task ahead of them.

Interest in Pacquiao—now 38 and well past his prime—has waned since he was dispatched by Mayweather, and pay-per-view numbers confirm that.

According to Bloody Elbow's Fraser Coffeen, Pacquiao's fight against Vargas was his least viewed bout since a 2008 contest against David Diaz. All told, the fight did somewhere in the neighborhood of 300,000 buys.

Based on those numbers and the fact that his next fight will reportedly occur outside of the United States, it wouldn't be a surprise to see viewership dip again.