NEW YORK — Although Gennadiy Golovkin can once again call himself a middleweight world titleholder after he defeated the rugged Sergiy Derevyanchenko over 12 memorable rounds at Madison Square Garden, the fight raised some questions about the long-term viability of Golovkin as an elite fighter.

The scores for this bout were 114-113, 115-112 and 115-112, and those close tallies don’t reflect just how tough a night it was for GGG. There was a time, just a few years ago, when he would’ve handled a fighter of Derevyanchenko’s level with ease.

Those days are over.

Now, just about every fight against a top-level opponent is a hard slog, with Golovkin toughing his way through and grinding his way to victory.

At the end of the day, though, it was a victory, and GGG walked out with a world title over his shoulder. A Canelo Alvarez trilogy is still on everyone’s mind, but did Saturday night’s bout help or hurt that possibility?

Let’s break down the biggest questions of the night.

How did GGG win the fight?

Golovkin won — barely. To be honest, just like last week, with Shawn Porter’s effort against Errol Spence Jr., you came away more impressed by the effort of the guy who didn’t get the nod. Although Golovkin is still a top-tier middleweight, he showed his age (37) in this fight. The hard years are beginning to show.

Although he still has heavy hands and solid technical skills, his reflexes and reaction time are noticeably slower. For long stretches in this bout, Derevyanchenko was able to beat Golovkin to the punch, and he landed a multitude of combinations to both the body and head, backing Golovkin up in the middle and late rounds.

Then again, every time the momentum began to swing in Derevyanchenko’s favor, Golovkin did just enough in certain rounds to take it back or at least win those stanzas on the cards. His conditioning, toughness and strength carried him through.

Is GGG getting a third fight with Canelo?

Golovkin thinks he is entitled to a third fight, given the fact that his multifight deal with DAZN called for a trilogy bout. It was initially supposed to take place in September, but Canelo wasn’t interested. Instead, Canelo will fight WBO light heavyweight titlist Sergey Kovalev on Nov. 2 in Las Vegas.

Putting all of that aside, as vulnerable as Golovkin looked tonight, Alvarez and Golden Boy might not walk but run to make a third fight with Golovkin. What is there to fear if you’re Canelo? Golovkin was a slower, aged fighter who got hit an alarming amount of times against a fighter in Derevyanchenko who has never been known to have particularly fast hands. At this point, you’d have to think Canelo would be a prohibitive favorite over his archrival.

The plan before Saturday’s fight was for Golovkin to make a quick return to the ring in January or February 2020 to take care of the IBF mandatory nice and early so that he doesn’t get hampered by that obligation later in the year. But we’ll have to see how much damage Derevyanchenko did Saturday, as both fighters headed to the hospital after the fight.

If Golovkin is able to take such a fight and win, a Cinco De Mayo weekend date with Canelo could be in his sights.

Then again, Canelo said Sept. 18 that he has closed the GGG chapter of his career. We’ll see.

Golden Boy signed a record-setting deal for Canelo with DAZN, with a clear commitment to put him up against Golovkin again. What isn’t clear is if that came without the consent of Alvarez, who is as headstrong as he is talented.

Can this GGG beat Canelo?

In a word, no. Every fighter has a point of diminishing returns, physically, and Golovkin is at that stage. Nobody is saying that it would be a blowout — Golovkin is still far too savvy and tough for that to happen — but the fact of the matter is that Alvarez is among the very elite prizefighters in the sport and is in his prime. He seems to be at the peak of his powers, and Golovkin is clearly on the descent.

Golovkin doesn’t seem to have the power he once had — perhaps his legs are no longer as stout. Alvarez is spectacular.

Is there a satisfying fight left for GGG that isn’t Canelo? If so, what is it?

I might be in the minority, but I think a bout against WBO belt-holder Demetrius Andrade is intriguing. It’s the classic pairing of the offensive juggernaut in GGG and the slick, tricky southpaw in Andrade.

In many ways, it would be a career-defining victory for either man. For Golovkin, it would confirm that he is still no worse than the second-best middleweight on the planet, and it would make him a unified titleholder again. For Andrade, a win over GGG would be exactly the type of victory that would catapult him into more marquee fights.

There is also the option of Golovkin moving up to super middleweight, where the likes of Billy Joe Saunders — a natural middleweight — and Callum Smith are both titleholders.

But based on what took place Saturday, there has to be clamoring for a rematch with Derevyanchenko as well, as he absolutely pushed Golovkin to the brink.

Where does Derevyanchenko go from here? Who’s next for him?

Derevyanchenko is still a solid middleweight — he came into this bout ranked sixth in the division by ESPN — and though his record drops to 13-2 (10 KOs), his only defeats have come in close fights to Golovkin and Daniel Jacobs. His stock now rises despite the defeat.

It will take a certain level of fighter to topple him. Moving forward, he will continue to get meaningful fights because he has gained some notoriety from his high-profile encounters. Derevyanchenko brings a straightforward style that generally makes for solid fights, and at this moment, he’s a great barometer of where a fighter stands in the division.

It isn’t out of the realm of possibility that Derevyanchenko could get a crack at Jermall Charlo, who has a version of the WBC belt. For Charlo, it would represent his sternest test to date as a middleweight. According to his promoter, Lou DiBella, they are free and clear of any network ties, so they are free to fight wherever they’d like.

Biggest takeaway from the undercard?

The fights were short, and the interludes were long. To be frank, this card featured some really good prospects in some pretty bad mismatches. Ali Akhmedo (who blew out Andrew Hernandez in one round) and junior middleweight Brian Ceballo (who stopped Ramal Amanov in three rounds) shined, and Ivan Baranchyk showed that he remains a formidable 140-pounder by blasting the light-hitting Gabriel Bracero in four.

But the most intriguing young fighter on this card was Israil Madrimov, who improved to 4-0 (four KOs) with a fifth-round TKO of the seasoned Alejandro Barrera (29-6, 18 KOs), who has been in with some solid opposition in the past. That résumé includes Spence, whom he fought in November 2015 and who had been the only fighter to stop Barrera coming into this weekend.

Joel Diaz, who trains Madrimov, says Madrimov is the best natural talent he has ever worked with and has traits that remind him of Vasiliy Lomachenko (with his footwork and angles), Terence Crawford (his ability to switch hit) and Golovkin (for his strength and power). But on Saturday, Diaz wasn’t all that pleased with Madrimov’s effort.

“I wasn’t that happy,” Diaz said. “I thought he was falling in too much and not getting clean shots. I told him, ‘Stop falling inside too much, get back to basics, and step back a bit and throw straight punches.'”

In Diaz’s estimation Madrimov was trying to do a bit too much and had to stick to basics. In his blasting Barrera you saw the talent, but you also saw that he still has a ways to go.