Father Time is undefeated.

So is Naoya Inoue.

But at 32, Inoue is already alluding that the pesky issue around age could be catching up to him as he prepares for his fight Saturday against David Picasso in Saudi Arabia as the headliner at "The Ring V: Night of the Samurai" show on DAZN PPV.

Inoue (31-0, 27 KOs) is still operating at the peak of his powers. He is the undisputed junior featherweight champion and a perennial top pound-for-pound player.

“The Monster” realizes, however, that he’s not invincible like Father Time, just as a potential changing of the guard looms if he gets past Picasso to fight fellow Japanese juggernaut Junto Nakatani in May.

“I absolutely can't afford to lose,” Inoue said on DAZN's "On The Ground" series.

“My motivation comes from the position I hold in the division. I've achieved results that satisfy me. But now that I am 32, things start to become more apparent. The subject of retirement — the fact that I'll retire someday — is something that's becoming visible at this stage.

“Being booked on the same show as Junto Nakatani, the fans will be looking ahead to next year with high hopes. So I need to show them that I'm still in the mix. Both of us winning is the top priority.”

Nakatani (31-0, 24 KOs), a three-division champion, will be making his 122-pound debut in the co-main event against Sebastian Hernandez.

Nakatani, 27, is regarded as Inoue’s successor to the throne.

Inoue has held titles in four weight classes after kicking off his career at 108 pounds; he’s been fighting at 122 for more than two years. He's 7-0 in the weight class and has defended his undisputed title five times, most recently in September against Murodjon Akhmadaliev.

The win against Akhmadaliev marked just the fourth time in Inoue’s illustrious 13-year career that he heard the final bell. Preceding the Akhmadaliev encounter were a pair of knockdowns during a four-fight stretch. The shocking sequences kickstarted conversations questioning Inoue’s chin and durability as he continued crusading in higher weight classes.

As the chatter gets louder amidst dangerous challenges, Inoue’s father and trainer, Shingo, is also increasingly talking about the “r” word as well while they prepare for Picasso (32-0-1, 17 KOs).

“Considering his age, I don't think he has much time left,” said Shingo. “I don't know how many more fights there will be, but it would be good if he can just perform in those remaining fights with real intensity and conviction, without any regrets. I believe that if he does that, the results will inevitably follow.”

Inoue will be fighting for the fourth time this year after gracing the ring twice each from 2021-24. But Inoue has already stated that he’ll likely fight just twice in 2026, and that the long-discussed move to 126 pounds is an afterthought now that that dangerous Nakatani waits in the wings.

“When it comes to featherweight, my weight isn't quite high enough yet, and physically there are still areas of concern,” said Inoue. “It's precisely because I have these feelings of both anxiety and excitement that I want to challenge myself in those areas, too.

“As long as I am performing at a top level, I've got my pride. If that sense of satisfaction, that feeling, starts fading, that's probably when you start weakening as a fighter.

“Once you stop challenging yourself, it's over.”