Saturday, Jan. 13, was a busy day for the world of combat sports. Eyes were glued to the TV and streaming devices with two back-to-back events scheduled - UFC Vegas 84 and Artur Beterbiev vs. Callum Smith boxing match.Find out the most interesting news updates of the day with Sportskeeda's daily news roundup.#3 Jim Miller calls out Brock Lesnar for UFC 300Since Anthony Smith brought it up, Jim Miller has been excited about the prospect of fighting Brock Lesnar inside the cage. After a submission win over Gabriel Benitez at UFC Vegas 84, Miller called out three fighters for a potential appearance at UFC 300 - Lesnar among them.Watch Miller's post-fight interview below: While the fight will never materialize in the promotion, given the stark difference between their weight classes, it makes one wonder if a surprising matchup like this would make the former heavyweight champion consider a return.Miller also called out Paul Felder and Matt Brown. Both seemed eager to honor his call-out, but Felder pointed out what could go "terribly wrong" if he decides to return.Whether Miller will feature on UFC 300 is not confirmed, but Dana White made a promise about it to TNT Sports' Adam Catterall.#2 Andrei Arlovski loses Waldo Cortes-Acosta's respectDuring their fight at UFC Vegas 84, Waldo Cortes-Acosta was seen taunting Andrei Arlovski inside the cage. Cortes-Acosta later explained his actions in the post-fight press conference."I talking to him because he was mad in the second round. You see guys - he tried kicking my mouthpiece. I respect him, (but) from that time, I respect no more."Watch Cortes-Acosta's comments below: Arlovski is a veteran of 59 MMA fights, winning 34 and losing 23 - two were declared 'No Contest'. His loss to Cortes-Acosta was his third straight, after losing to Don'Tale Mayes and Marcos Rogerio de Lima.#1 Alex Pereira to fight Magomed Ankalaev next?After Magomed Ankalaev secured a knockout win over Johnny Walker at UFC Vegas 84 and settled their rivalry from the previous 'No Contest.' Glover Teixeira readily tweeted:"Great knockout. We will see u soon."Teixeira is not only a training partner and mentor of Alex Pereira, the reigning light heavyweight champion, but is also close friends. The above message, sent to Ankalaev on 'Poatan's' behalf, could very well be a hint that Teixeira is hoping to defend his belt against the Russian next.In response, Ankalaev gave a brief but positive reply - both via X and the post-fight press conference.