Jermall Charlo returned to the ring after an 18-month layoff for just his second fight in the past four years and looked incredibly sharp, knocking down Thomas "Cornflake" LaManna three times before forcing a stoppage in the fifth round Saturday night at Las Vegas' Mandalay Bay Resort and Casino.

Just a few weekends ago, boxing fans and promoters were reminded of the risks of scheduling popular fighters in tune-up fights prior to matching them against each other. On Saturday, Caleb Plant and Jermall Charlo will look to avoid the pitfalls faced by Devin Haney and Ryan Garcia with the intent to make a big showdown later this year.

May has been a month of major upsets in boxing — and Armando Resendiz's shocking victory over Caleb Plant may be the biggest of them all.