Getty Images

A pair of world titles and a must-see action rematch headlines the UFC's return to Singapore on Saturday at UFC 275.  

Glover Texieira makes the first defense of his light heavyweight crown in the main event against hard-hitting Jiri Prochazka. In the co-main event, Valentina Shevchenko aims for the seventh defense of her women's flyweight title when she welcomes Taila Santos.  

But the most anticipated bout on the card just might be a rematch of the greatest female fight in UFC history when former 115-pound champions Zhang Weili and Joanna Jedrzejczyk meet in a sequel to their 2020 classic.  

Let's take a closer look at the biggest storylines entering this weekend. 

Can't get enough boxing and MMA? Get the latest in the world of combat sports from two of the best in the business. Subscribe to Morning Kombat with Luke Thomas and Brian Campbell for the best analysis and in-depth news, including the top storylines to watch at UFC 275 below.

1. Will it be one and done for the ageless wonder as champion? 

Teixeira delivered one the most memorable feel-good moments in MMA history when, at 42, he submitted Jan Blachowicz last October for his seventh straight win to finally capture UFC gold. Teixeira's story is a testament to his hard work, values and inability to give up hope that hard work would go unrewarded. But as good as that moment was, things only get more difficult from here as Teixeira welcomes the dangerous and unpredictable Prochazka. The 29-year-old former RIZIN champion will get his first shot at UFC title in just his third trip to the Octagon after debuting in 2020, but the pair of knockouts he delivered against Volkan Oezdemir and Dominick Reyes, both after absorbing punishment early on, was an eye opener to the rest of the division. Prochazka is a small betting favorite as the challenger given his ability to end a fight at any given moment. But the Czech native also takes big chances and leaves himself vulnerable, which is something a wily veteran like Teixeira can potentially capitalize on. That remains a big if, however, given the danger he will need to circumvent in order to get there.

2. Santos presents an interesting challenge to Shevchenko's dominance 

Remember that time MMA fans and critics thought former strawweight champion Jessica Andrade possessed the greatest threat to Shevchenko's dominant 125-pound title reign only to see her viciously stopped by elbows on the ground in 2021? The result was a testament to Shevchenko's insane work ethic and the fact that she's never lacking in motivation to prepare to be at her best. Given how one-sided the majority of Shevchenko's title defenses have been, it has been somewhat difficult to get excited about each title defense for the top rated women's pound-for-pound fighter. Santos, a native of Brazil, does offer the potential to suspend one's misgivings. After losing her UFC debut via split decision against Mara Romero Borella in 2019, the 28-year-old Santos has won four straight, including a dominant first-round submission win over Joanne Wood in November. Will Santos be the one to put an end to Shevchenko's growingly historic reign? Let's not go that far, necessarily. But the good news is that Santos is a physical and dangerous presence, one that Shevchenko will need to approach with care. Unlike most of Shevchenko's recent title challenges, there is a potential path to victory fans could imagine for Santos provided the conditions of the fight went her way, which is why Santos remains around a +450 underdog, which might be the best odds a Shevchenko opponent at flyweight could hope for.

3. Is it time for Shevchenko to return to 135 pounds? 

Should she dominate Santos to the same degree she has handled her six title defenses since outpointing Jedrzejczyk for the vacant flyweight title in 2018, the answer might be yes. Shevchenko has long coveted a rare third chance at facing current featherweight champion and former 135-pound queen Amanda Nunes, who owns a pair of victories over Shevchenko at bantamweight, although their 2017 title rematch remains largely disputed. Nunes will face new 135-pound champion Julianna Pena, who upset her last year, in a July 30 rematch and Shevchenko has openly coveted the idea of moving back up to bantamweight to face the winner to close 2022. Should she handle Santos with ease, it's very likely Shevchenko could get her chance at cementing her legacy and making her case for being the greatest of all-time.  

4. Who enters Zhang-Jedrzejczyk II as the fresher fighter?  

It's a question worth debating after the now former 115-pound champions first met in a savage five-round war just two years ago, which Zhang won by split decision for her first (and only) strawweight title defense. Both fighters accrued tremendous punishment throughout a fight in which neither was willing to take a backward step. Jedrzejczyk, in particular, showed the physical damage much more with the grotesque hematoma she developed on her forehead that somehow did nothing to halt her forward progress. Since the fight, however, Jedrzejczyk has yet to return to fighting, which should either leave the 34-year-old refreshed upon her return or open up the potential for cage rust. Zhang, who is two years younger yet has two more pro fights than her opponent, has been much busier. That hasn't meant she has won a fight since then, suffering consecutive defeats to former two-time champion Rose Namajunas, including the first via head-kick knockout in Round 1. Given the unknowns between them, the expectation for two-way action remains high. It's just difficult to know who has the edge, especially since Zhang's narrow victory in the first fight. The fight is also heavily anticipated because UFC president Dana White has declared the winner will get a shot at the title, now worn by inaugural champion Carla Esparza following her victory over Namajunas in their recent rematch.

Who wins Teixeira vs. Prochazka? And what other picks do you need to see? Visit SportsLine now to get detailed top picks on UFC 275, all from the insider who's up more than $10,000 on MMA picks the past two years, and find out.