Floyd Mayweather Jr. and Manny Pacquiao are at it again, getting fans excited about a super fight. While the matchup now lacks much of the sizzle it would've had years ago, when the two were clearly the best fighters in the sport, it remains a highly-sought after matchup.

Fans are still debating the merits over one fighter or the other, and even though Pacquiao has suffered two defeats since they co-ruled the pound-for-pound rankings, Mayweather looked less than invincible in his two latest bouts vs. Marcos Maidana.

Pacquiao fired the latest shot via Twitter.

Should we all get our hopes up? I say no, but will also play devil's advocate.

These are the biggest reasons Floyd Mayweather and Manny Pacquiao will probably retire without having faced one another.

Money, Money, Money

One of the major sticking points throughout the years between these two is money. Mayweather's nickname is "Money," and he insists on making the most in any situation. He has billed himself as the greatest fighter of all time, and he's inarguably the sport's top draw.

Pacquiao has always believed himself to be on Mayweather's plane in terms of star power-several years ago he may have had a point. Now, however, his PPV numbers lag behind Mayweather's for a number of reasons. Mayweather will probably force an unpalatable purse split onto Pacquiao, and make it difficult for the fight to be made.

Glass Half Full: Even a borderline insulting slice of this purse could potentially be greater than a better fight in which Pacquiao is treated as an A-side. Pacquiao swallows his pride, accepts, and we have ourselves a fight!

Bob Arum

Bob Arum still runs Top Rank Promotions, and Floyd Mayweather Jr. hasn't indicated he yearns to re-ignite their professional relationship. Time and again Mayweather has stated he will not work with Arum ever again.

That flies in the face of what Mayweather said on Showtime this past Friday, when he challenged Pacquiao and said "Let's make it happen." Boxing involves a lot of boasting and showmanship. This very well could be some showmanship-an effort to show the world that he "tried."

The simple fact is that he broke away from Bob Arum because he believed he could make drastically make more money with his own team. For this fight to work, Mayweather and Arum will have to play nice.

Glass Half Full: Mayweather looks around and sees nothing but Amir Khan. Mayweather, with two fights left on his Showtime deal and possibly in his career, decides life is too short to hold grudges. He holds his nose, works with Arum, and makes more money than he did even when he fought Oscar De La Hoya.

Canelo Alvarez

Whoa, wait...didn't Mayweather dismantle Alvarez in 2013? That's correct-but the dominant performance didn't ruin Alvarez's star power. Since the Mayweather fight Alvarez has remained a fan favorite, putting up good PPV numbers against the likes of Alfredo Angulo and Erislandy Lara.

Alvarez is planning on fighting Puerto Rican superstar Miguel Cotto on May 2. That's the same night Mayweather is pushing for to face Pacquiao. To have cards that massive competing against one another would be foolish for all parties involved, and Alvarez has been steadfast that he won't back off May 2.

That weekend is the weekend of Cinco de Mayo; Canelo has vowed to reclaim that date for his countrymen from Mayweather, who has re-named it Cinco de Mayweather. Should Alvarez really dig in his heels, that could derail everything.

Glass half full: Golden Boy president Oscar De La Hoya convinces Alvarez he's the future of boxing even if he backs off Cinco De Mayo for one more year. He sells Alvarez on Mayweather-Pacquiao growing the sport, leaving a bigger pie for Alvarez to devour as his career moves forward. The fight goes on as Mayweather wishes, and boxing fans get both fights.

Amir Khan & Oscar De La Hoya

It has never come across that Oscar De La Hoya and Floyd Mayweather are BFFLS, but they've done plenty of business together. Amir Khan may have a questionable chin and some ugly losses on his resume, but each time Khan wins those losses fade away.

Khan has an enormous British and Middle Eastern fan base, a sizable name in the sport, and a skillset that is different from Mayweather's last several opponents.

More importantly, Khan's legacy is far from written. He is hungry for a major fight to vault him into superstardom whereas Manny Pacquiao is descending from the mountaintop. Mayweather can make a lot of money with Khan, and make a greater chunk of that money with little more than a peep from Khan's team.

Plus, he's already a Showtime guy so that cuts out the money and headache of figuring out the pot with HBO and Top Rank. If the money is close, do not think for a second Mayweather wouldn't sign on to face Khan.

Glass Half Full: Come on...Amir Khan? That fight isn't approaching Mayweather-Pacquiao money.