Key questions for Crawford-Porter: Porter's aggression the difference? Is Crawford done with Top Rank?

Terence Crawford defends his WBO welterweight championship against Shawn Porter on Saturday (ESPN+ PPV, 9 p.m. ET), and Crawford, ESPN's No. 2 pound-for-pound fighter, has a lot on the line. Beyond his title, his undefeated record is at risk in one of the biggest challenges of his career. How will Porter's aggression be a factor? And could it lead to a KO, one way or the other?

If Crawford does successfully defend his title, it will raise a number of new questions as well. It's the last fight on his Top Rank Boxing contract, and if he's going to remain at 147 pounds in the long term, the competition at that weight resides under different promotional banner. The other two welterweight champions, Errol Spence Jr. and Yordenis Ugas, fight for PBC. So will Crawford jump ship, and if so where will he go? The Spence fight in particular has been one that boxing fans have long been after. With a win, and potentially a promotional change, could it finally be realized?

Heading into Crawford-Porter fight week, Mike Coppinger and Ben Baby break down some of the biggest questions surrounding the bout. Then key figures in the fight world, Ugas and Ray Beltran, give their thoughts on a potential KO.

If he wins, does Terence Crawford finally get to fight Errol Spence Jr.?

Coppinger: With Manny Pacquiao retired and Crawford on the final fight of his long-term Top Rank deal, it would appear a victory would bring Crawford closer than ever to the elusive Spence fight. But it's still difficult to convey any genuine confidence in a deal being finalized in the next year.

Rather than engage in talks to fight each other, Crawford and Spence circled Pacquiao on their respective hit lists; "Bud" was in talks to fight Pacman last year and Spence was signed to fight him before the fight fell apart when Spence suffered a detached retina.

Spence is now recovering from surgery and appears poised for a spring bout with Ugas, who defeated Pacquiao in August. Crawford, meanwhile, could have newfound flexibility for a potential fight with Spence. A multifight deal with PBC would bring him closest to the megafight, but remaining a promotional free agent also could allow him to secure it.

His alliance with Top Rank was always the biggest impediment to the bout. Whether Spence and Crawford actually yearn for the fight is another matter altogether. Crawford has repeatedly said he's moved on from the Spence matchup; Spence never showed a ton of interest in the fight to begin with.

Will Terence Crawford re-sign with Top Rank?

Coppinger: All signs point to Crawford departing Top Rank after the fight with Porter.

The welterweight champion has long been frustrated with Bob Arum's ability to deliver the Spence fight, though the promoter did finally come through with the Porter matchup. And it wasn't cheap, with $10 million in guarantees ($6 million to Crawford).

Top Rank has paid Crawford handsomely, and Arum wasn't shy last year about his own issues with the arrangement.

"The question is, do we want to keep him? I could build a house in Beverly Hills on the money I've lost on him in the last three fights," Arum said ahead of Crawford's win over Kell Brook.

Besides whatever acrimony may exist, there's the greater issue of available opponents for Crawford. Jaron "Boots" Ennis, a rising star in the welterweight division, has competed exclusively on Showtime, though he isn't signed with Al Haymon and could compete elsewhere. Vergil Ortiz is with Golden Boy. But beyond Ennis and Ortiz, the majority of the top 147-pounders are with PBC, including Spence, Keith Thurman (whenever he returns) and Ugas.

Short of a monetary offer Crawford simply can't refuse, it's hard to see the relationship with Top Rank extending into 2022.

Can Porter's aggression give Crawford problems?

Baby: Definitely. Aggressive fighters require boxers to be at their absolute sharpest. And Porter represents a challenge Crawford hasn't seen in recent fights. In Crawford's last five bouts, his opponents have averaged just 36 punches per round, according to ESPN Stats & Information. Porter, on the other hand, lets 54 punches go every round.

Crawford has also been slightly more susceptible at welterweight, too. The undefeated champion was unofficially knocked down in his 2019 victory over Egidijus "Mean Machine" Kavaliauskas. Given Crawford's delayed response, it wasn't ruled accordingly, but the replay looked more convincing.

Porter's pressure will require Crawford to be mentally and physically engaged for the entirety of the fight. It's the biggest advantage to being a pressure fighter. But if Crawford can use that aggressiveness against Porter, much like Brook did in their 2014 bout that resulted in Porter's first loss, Crawford will remain undefeated and pick up the biggest win of his welterweight run.

What's the best fight on the undercard?

Baby: Fight cards seemingly aren't what they used to be, even big pay-per-view cards like this one on ESPN+. So, finding the second-best fight on the Crawford-Porter undercard requires some imagination.

There is some intrigue surrounding undefeated middleweight Esquiva Falcao's bout against Patrice Volny (16-0, 10 KOs), a Canadian making his United States debut. Falcao (28-0, 20 KOs) most recently stopped Artur Akavov in the fourth round on the Miguel Berchelt-Oscar Valdez undercard.

Falcao is the No. 10 middleweight in ESPN's ranking (it's worth noting that Janibek Alimkhanuly, who is ranked eighth, is also on the undercard, but he is fighting a very aged Hassan N'Dam). This could be another showcase for Falcao, who is angling for a title fight in the near future.

How likely is it that this fight ends in a KO?

Yordenis Ugas: I don't think there will be a knockout -- anything can happen in that fight, they are both very strong fighters, but I don't see a knockout. I do know that it will be a very competitive and close fight for all 12 rounds.

Ray Beltran: Of course it can be a KO. The best chance for Porter is to get a KO in the first three or four rounds. Crawford can get a KO too, because while Crawford uses his distance pretty well, and is a master at that, he likes to pressure and knows how to do that well, too. He's so smart. I wouldn't be surprised if Crawford stays in front of Porter and gets the KO.