Some will kick him when he's at his lowest ebb, but former champion Anthony Joshua has the ability to put it all together yet again

There are only three certainties in life: Death, taxes and a 30-something boxer who just lost by knockout being asked if he'll retire.

And so, naturally, much of the buzz after the fantastic IBF heavyweight title fight between champion Daniel Dubois and former champion Anthony Joshua on Saturday in London centered on whether we'd seen the last of Joshua in a prize ring. Dubois dropped Joshua four times Saturday and knocked him out at 59 seconds of the fifth round.

The answer, thankfully, is no. Joshua made a brief appearance at the post-fight news conference on Saturday and said he would continue to box. He posted a video to social media on Monday in which he reiterated his intention to continue.

Joshua, of course, doesn't need to fight. He's rich beyond his wildest dreams and his children's grandchildren should be set for life if he never pulls a glove over his fist again. Elite professional athletes get to where they are, however, because they're competitive to a fault, and they believe in themselves so thoroughly.

It wouldn't make sense for him to fight if he couldn't get a bout of significance or if he couldn't land a major payday. That's not the case in this situation. 

The worst case scenario now for Joshua is if Tyson Fury defeats Oleksandr Usyk in their rematch for the unified heavyweight title on Dec. 21 in Riyadh. If promoters wanted to pit the winners for the undisputed title, that'd mean Fury would then meet Dubois for all the belts.

But that scenario isn't great for Joshua because he's already lost twice to Usyk and it doesn't seem like there's either a reason or a demand to see that again. It's also quiet possible that if Fury defeats Usyk on Dec. 21 that they'll meet for a third time to settle their rivalry in a rubber match.

The best case scenario for Joshua would be for Usyk to win the Fury rematch on Dec. 21, because then that would set up a fight between he and Fury, literally and figuratively the giants of the modern British boxing scene.

He will turn 35 on Oct. 15, but he doesn't have a lot of miles on the body. He's also been in magnificent physical condition, and he was again on Saturday in the KO loss to Dubois. That allowed him to last into the fifth round, even though Dubois caught him with a crushing right hand early the first round. Were he not in fabulous condition, he wouldn't have been able to come back after that.

His promoter, Eddie Hearn, insisted that Joshua has a rematch clause, even though Dubois promoter Frank Warren says the opposite. Hearn and the team clearly babied Joshua and Hearn came to the post-fight news conference and solemnly announced that he'd advised Joshua not to attend. He said Joshua wanted to speak to the media, but Hearn then insisted he take no questions.

Now, given that Joshua was perfectly fine an hour after the fight, that was excessive. Joshua did appear and acquitted himself well in his post-fight remarks, even if he left without taking questions.

Hearn, though, is right to be concerned to a degree, because Joshua took a lot of head shots.

"To be honest with you, it's probably the only time in his whole career I've seen him really hurt," Hearn said. "So it's not bad. Having won two world heavyweight championships, 13 world heavyweight championship fights and that's the only time he's really been hurt to the point he couldn't get up. Heavyweights get knocked out all the time. You never want to see a heavyweight get knocked out, but that was the first time in his career he's been properly hurt. So, you never want to see it and you never want to carry on too long. But at the same time, A.J. is a heavyweight who doesn't have a lot of miles on the clock, in all honesty."

Trainer Ben Davison said the start dictated the rest of the fight, and that Joshua couldn't fully implement the plan in the latter stages because "he wasn't thinking clearly." But Davison said when Joshua came to the corner after the fourth, he said something that indicated he was of a clear mind.

"These are the moments we live for," Davison said Joshua told him when he got to the corner prior to the fateful fifth round.

Davison is one of boxing's best trainers and he's done good work with Joshua. But while he insisted nothing Dubois did was a surprise and they had a plan to attack him that he believed would have worked, things went off-kilter once the first bell rang. Dubois was on a mission and when a 250-pound hard-hitting heavyweight cracks one on the chin, it often impacts the rest of the bout.

Davison was classy, though, as he accepted his share of the blame.

"I'd just like to say that me and my team have received a hell of a lot of credit for good performances that he had, so it's important that we accept responsibility for the bad performances, as well," Davison said. "So we're willing to do that."

Joshua had no complaints. In the video he released on social media on Monday, he not only reiterated that he would continue to fight but was smiling and quite upbeat.

He's near the end of his career because he's been doing it for so long and there's not a lot of opponents that make sense, at this stage. But he doesn't have to end on that downer of a note if he doesn't want to do so.

And hearing him speak Monday, it sounds as if we'll see him in the ring again very soon.

"Yesterday night, we came up short, but we've got to look at all the positives," Joshua said. "That's the mindset and that's the perspective that we have to have, a positive one. Always. Look at what we've achieved in the space of 11 years. It's been phenomenal. And I want to thank every single one of you who has been riding with me. What a roller coaster journey! The problem is, it's far from over yet. We done it once. We done it twice. Doing it a third time hasn't been easy, but I believe it's something I can achieve. It's about making the right steps forward, working hard, improving, and it's got to come from here [tapping his chest] more than anything.

"It can't come from any external voices or influences. It's got to come from here. It's only been a day but as I've been sitting back and thinking, I know I got a lot of this [tapping his chest again], man."

Joshua doesn't have the greatest chin, but no one who has ever watched him fight could ever question his heart.

He hasn't always made the right decisions in the ring, but the love of the fight has never been missing. And that, more than anything, is what almost certainly will bring him back soon in yet another mega-fight.