Canelo Alvarez has received plenty of criticism for his decision to face Liam Smith in his next bout on Sept. 17 on HBO PPV, including taking a verbal jab from UFC star Conor McGregor.

McGregor called out the former boxing middleweight champion for "cherry-picking" his opponents in order to maintain his record and avoid big challenges like Gennady Golovkin. Alvarez, unsurprisingly, did not take too kindly to McGregor's ribbing and has now issued a challenge to the UFC featherweight champion to step in the boxing ring with him.

"If he wants to try out boxing, then anytime he wants," Alvarez told reporters at a workout this week. "If he wants to come over to this side of the world and try boxing, anytime he wants to see that it's not as easy as he thinks."

This isn't the first time McGregor has found himself in a contentious battle of words with someone in another fight sport. McGregor was rumored to be interested in fighting Floyd Mayweather earlier this year and, most recently, has been in a war of words with WWE stars.

In this instance, most in the boxing world will side with McGregor on his comments. Canelo's decision to relinquish the WBC middleweight title in order to avoid a mandatory bout with Golovkin was disappointing, to say the least, to boxing fans hoping to see the two biggest stars of the sport meet in a superfight. Instead, he chose to drop down to super welterweight and face titleholder Liam Smith, who few expect to provide much of a test for Alvarez.

As for getting McGregor into the ring, that's about as far-fetched as Alvarez actually stepping in the ring with Golovkin in the next year, but it's some good talk.

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