It's extraordinarily difficult to win a UFC championship, and there have been many great fighters throughout the years who haven't been able to do it. How difficult it is to win, and then retain, a UFC belt may not be fully appreciated, though.

There are 12 divisions in the UFC, eight for men and four for women. Let's exclude women's featherweight for this argument since the UFC rarely puts on any women's 145-pound bouts of any type these days and consider the other 11. In that scenario, there are eight divisions in which there is either a championship vacancy (heavyweight) or where the champion has held the belt for less than a year.

Jon Jones and Ciryl Gane will fight for the vacant heavyweight title on Saturday in the main event of UFC 285 at T-Mobile Arena in Las Vegas. Brandon Moreno won the full flyweight title in January, moving up from interim champion, when he defeated Deiveson Figueiredo. Lightweight champion Islam Makhachev, welterweight champion Leon Edwards, middleweight champion Alex Pereira, light heavyweight champion Jamahal Hill, women's bantamweight champion Amanda Nunes and women's strawweight champion Zhang Weili have all won their titles within the last year.

Of that group, only Makhachev has made a successful title defense during his or her current reign.

And then, of course, there is flyweight queen Valentina Shevchenko, who is the UFC's longest reigning champion and has made made seven successful title defenses since first winning it from Joanna Jedrzejczyk on Dec. 8, 2018, at UFC 231 in Toronto.

Shevchenko will go for her eighth consecutive successful title defense three days before she turns 35 on Saturday in the co-main event when she puts the belt on the line against Alexa Grasso. Shevchenko came to the UFC in 2015 as an 11-1 bantamweight, even though she was significantly smaller physically than nearly everyone she met.

UFC didn't have a women's flyweight division at that stage and so Shevchenko fought up a class. She went 3-2 at bantamweight, which isn't the most impressive record until one digs a bit deeper. Four of her five fights at 135 pounds in the UFC were against former UFC champions: Two against Nunes and one each against Holly Holm and Julianna Peña. The fifth was against Sarah Kaufmann, a former Strikeforce champion.

Her losses to Nunes were close, particularly the rematch in Edmonton on Sept. 9, 2017, at UFC 215.

Since the UFC created the flyweight division, Shevchenko has gone 9-0 and has been utterly dominant. It wasn't until her last fight, against Taila Santos at UFC 275 in Singapore in June, that she even showed a hint of vulnerability.

She won a split decision over Santos that was disputed. Shevchenko said she's "comfortable" with her performance against Santos despite many fighters questioning the scoring favoring her.

Shevchenko says she didn't take Santos lightly, is prepared for the best Grasso the world has ever seen and still believes she's on the upswing.

Since impressively submitting former world champion Jessica Andrade, Erin Blanchfield has been speaking out about Shevchenko and making the rounds media-wise to make her case she deserves the next title shot.

Shevchenko is reticent to speak of Blanchfield, though, even though Blanchfield has spoken so much about her. If she wins on Saturday, she'll tie Jon Jones for fourth with eight consecutive title defenses behind only Demetrius Johnson (11), Anderson Silva (10) and Georges St-Pierre (9). She has such a single-minded focus that she refuses to even consider an accomplishment like that.

"I never want to start thinking about what is going to happen because then you start to overlook your [upcoming fight] and think about what may happen and when you do that, there's a good chance everything goes wrong," she told Yahoo Sports. "In my experience of 30 years in martial arts, I have learned the important thing is to focus only on one thing, what is going on in the ring [in my next fight]. Once you start to plan or dream about something else other than winning your fight, you lose sight of what your main focus is. Thinking about who I might fight next or what record or accomplishment I get is a way of distracting you and it's not right for the fighter."

The danger is that it leads to burnout. Champions are regularly fed the best available opponents and putting such intense focus on each opponent becomes a job in and of itself. It's why so many NFL coaches burn out from pushing themselves to work 18 to 20 hour days in pursuit of a championship.

Shevchenko laughs at the notion that she's vulnerable to that. She's multi-lingual and speaks Russian, Spanish and English fluently and is learning to speak Thai. She's an avid traveler, loves to shoot guns at the range and adores boating.

She'll mulling learning how to fly like her older sister, Antonina, has done.

Life is an adventure to be discovered and when she's out of camp, Shevchenko loves to tour the world in search of fun, adventure and education.

"It's easy [to keep my focus on my fights] because I have so many things I love to do," she said. "When it's time to work, I am all in for work. But there are these other things I love to do. I have a lot of interests beyond just training. I love traveling. I always want to see new things and experience the beauty of this world. I love to go to the shooting range and to drive my boat. I have many, many interests and so when you switch from one to the other, you're always refreshed and excited to do whatever it is you're about to embark on.

"So when I get back and it's time to train, I love it and I really look forward to it and I'm excited to do it because the martial arts have been a part of my life for so long. That way, I know I can fully dedicate myself and give my best [performance}."