Errol Spence proved doubters wrong on Sunday when he defeated former Welterweight ace, Shawn Porter. The 29-year-old southpaw slugger unified the IBF and the WBC welterweight crown and let the world know that "The Truth" is the real deal.

However, boxing fans have speculated that Spence is too slow and can be defeated by faster fighters. There is no doubt that Errol has tremendous power, with 21 of his 26 wins coming from knockouts.

However, he's not the fastest welterweights around and his defense needs to improve, especially against elite competition. Meanwhile, in the aftermath of his victory, local fans asserted that the next big fight for the American champ could be against Manny "Pacman" Pacquiao.

The reigning WBA welterweight champ has said before that he's willing to fight the winner of the Spence-Porter title bout. Manny has said that he plans to fight at least three times before calling it quits, and a match against Spence could be worth watching.

Errol Spence Jr. and Mikey Garcia
Errol Spence Jr. could be too much for Manny Pacquiao to handle if they do end up jostling next. (R-L) Errol Spence Jr fights Mikey Garcia in an IBF World Welterweight Championship bout at AT&T Stadium on March 16, 2019 in Arlington, Texas. Getty Images/Tom Pennington

After beating Keith Thurman on July, Pacquiao said that he plans to have a rematch against Floyd Mayweather. Despite his attempts, Jr. only managed to showcase an alleged "exhibition" match against the Filipino pugilist.

Pacquiao has since reiterated that he's only interested in a real boxing match. His camp has already listed Danny Garcia, Mikey Garcia, Amir Khan as potential opponents, including the winner of the Spence-Porter match, which was won by Errol.

In any case, Spence could also choose from the list above; there are even rumblings that "The Truth" could face Danny "Swift" Garcia. On Sunday, Danny made a special appearance on the ring urging the newly crowned IBF and WBC champion to fight him next.

But it wouldn't make as much noise as Spence versus Pacquiao. The 40-year-old Filipino boxer has made a resurgence as of late, winning five of his six fights against younger competition. His only loss came from a controversial match against Australia's Jeff Horn.

Pacquiao has a solid fanbase, meaning that his fights usually sell well and generate the right amount of racket. Manny has a proven 67-7-2 record and at his advanced age, he could still perform at a high level.

Boxing analyst, Nissi Icasiano believes that this fight could be very entertaining. He said that "on paper, Spence is too strong, skilled and young... but the Spence who showed up in the ring with Porter last weekend" will be in a lot of trouble against "Pac."

There is no doubt that Errol's defense needs a lot of improvement. Manny could easily find those weak points and capitalize, given that Spence struggled against Kell Brook and Shawn Porter.

If the fight pushes through, there is no doubt that it will sell. Pacquiao-Spence will be an exciting fight to watch.