Showtime boxing's summer series continues to bring the heat with another pair of title fights on Saturday night. Hosting a split-site doubleheader, Showtime will feature a pair of champions looking to make their marks in Adonis Stevenson and Gary Russell Jr. But the two face stiff challenges in Badou Jack and Joseph Diaz Jr.

The champion Stevenson (29-1, 24 KOs) will be returning to the ring for the first time in nearly a year. The last defense of his WBC light heavyweight title took place last June where he stopped Andrzej Fonfara via TKO in the second round. That was Stevenson's eighth consecutive defense of his championship since he earned it by quickly knocking out Chad Dawson back in 2013. He remains one of the top 178-pound champions despite noticeably avoiding the likes of Sergey Kovalev and now-retired Andre Ward.

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Jack (22-1), meanwhile, is once again playing in the underdog role entering this latest bout. He last entered the ring last August as part of the Mayweather-McGregor undercard, and did not disappoint. The former super middleweight champion defeated Nathan Cleverley via TKO in the fifth round to capture the WBA light heavyweight title. Jack would end up vacating the WBA 175-pound title in late September, but now he's looking for more championship gold on Saturday night if he can stop the run that Stevenson has been on.

Below is all the information you need to catch the light heavyweight championship clash between Stevenson and Jack on Saturday. 

Stevenson vs. Jack viewing information

Date: Saturday, May 19
Time: 9 p.m. ET | Location: Air Canada Centre -- Toronto, Canada
Live stream: Sho.com | TV channel: Showtime (check local listings)