By Jake Donovan

Several challenges are in store for Floyd Mayweather on Saturday evening, not all of which exist in the ring. Conversely, the more difficult challenge for the sport's pound-for-pound king may not come from the fists of Robert Guerrero, but from his ability to carry an event on his own.

Tonight's pay-per-view event serves as Mayweather's debut with Showtime after having spent the majority of his career on longtime industry leader HBO. Showtime has dramatically closed the gap between the two, even winning in the ratings during dueling televised cards on April 27. 

Still, this pay-per-view telecast comes without a marketable B-side - Guerrero's story is well-known in boxing circles, but hardly a mainstream attraction. The show also serves as the first time since 2009 in which Mayweather will not benefit from Saul 'Canelo' Alvarez serving as part of the supporting cast.

The show was originally designed for the two to appear in separate bouts. However, Alvarez opted out after unsuccessfuly securing a guarantee from Mayweather and the event's handlers that a head-on collision was in store for September.

That leaves Mayweather's name to carry the show. 

Will it be enough to continue his current run of surpassing the one-million pay-per-view units sold plateau (which also happens to be the unofficial break-even point)? 

Read on to see how the staff at Boxingscene.com believes tonight's major event will fare at the box office.

B-SCENE STAFF PREDICTIONS: 'MAY DAY' PAY-PER-VIEW UNITS SOLD

"1.4 mill"
- Damien Acevedo (over 1 million)

"Pre-fight program ratings aside, there's no denying that Showtime and CBS have done a hell of a job in promoting the product, as well as Swanson Communication and Golden Boy Promotions. People don't necessarily need to watch every show to know an event is going on; awareness is enough to segue to intrigue. Along with maintaining his '0', Floyd will also remain the sport's most bankable fighter, pulling in 1.25 million buys. Not enough for the record books, but enough for everyone to enjoy a profit." 
- Jake Donovan (over 1 million)

"I'm not sure it's the competitive match that Mayweather/Cotto was, but I think Guerrero's done a good enough job of selling the fight that it'll get to a range somewhere between 800K and a million buys."
- Lyle Fitzsimmons (under 1 million)

"Mayday will do 675,000 buys and will not be formally announced." 
- Ernest Gabion (under 1 million)

"1.1 million"
- Ryan Maquinana (over 1 million)

"MAY DAY May 4 Pay-Per-View show will do 1.2 million buys."
- Richard Najdowski (over 1 million)

"Is this the fight where Floyd dips below a million buys?  Considering all the exposures its had, that would be a bit of an upset.  It won't match Cotto, but let's go 1.1 (million)."

- Cliff Rold (over 1 million)

"One million buys. This fight is relying solely on Mayweather's name alone and without Saul Alvarez on the undercard to lend a hand, Mayweather's drawing power will be tested. Money however is indeed the sports biggest draw and with the help of CBS, Showtime, All Access and his two documentaries, it will be enough to keep Floyd's PPV buys in the 7 figures."
- Luis Sandoval (Even)

Totals: Over 1 million - 5; Under 1 million - 2; Even - 1

Jake Donovan is the Managing Editor of Boxingscene.com, as well as a member of Transnational Boxing Ratings Board, Yahoo Boxing Ratings Panel and the Boxing Writers Association of America. Twitter: @JakeNDaBox