The countdown is on with the finish line officially in sight for undefeated welterweight champion and pound-for-pound king Floyd Mayweather, Jr. He enters the first of his final three fights this weekend at the MGM Grand Garden Arena in Las Vegas before calling it a career next September.

For Mayweather (46-0, 26 KOs) to escape the 2014 calendar year undefeated and straps intact, he’ll have to get through a familiar opponent in Argentina’s Marcos Maidana (35-4, 31 KOs), who gave Mayweather all he could handle this past May in a closely-fought contest that resulted in a majority decision for the champion.

The question now entering Saturday night’s title fight is whether or not Maidana can learn from his shortcomings the last time out and become the first fighter in history to hand Mayweather a loss on his pristine resume.

"I don't think Maidana is on Floyd's level," renowned boxing oddsmaker Joey Oddessa tells Covers. "Throw scorecards out the window. Sure, Maidana gave Floyd fits at times with roughhouse tactics, but Floyd is the best in boxing at adjusting after a few rounds and ultimately taking control of fights. It's really hard to imagine Maidana doing any better than he did in the first fight and, outside of a criminal decision, Floyd's not going to lose even if the judges try to score rounds for the underdog."

While some believe that Mayweather is ripe for a fall - and that Maidana is the perfect candidate to successfully seize such an opportunity - others attribute that close call last May to a distracted Mayweather, who had broken off his engagement with fiancée Shantel Jackson in the days leading up to the bout.

"Mayweather's entire life outside of the ring has been a distraction," says Oddessa. "If there was ever a guy who was contradictory in all of sports it may be Floyd Mayweather. The media's portrayal of his actions outside the ring would lead bettors to believe he wouldn't be as great as he is and been due for a letdown for years. Hindsight is 46-0. We see how that logic has turned out."

Listed as high as +850 the last time around, bookmakers are giving more respect to Maidana for the rematch. The Argentinian knockout artist can currently be purchased for a price of anywhere from +525 to +600.

When it comes to boxing, the key, however, is to know when to fire on your fighter of choice.

"The best time to bet an underdog in a big fight is generally as early as possible," Jeff Sherman, assistant sportsbook manager at the Westgate Las Vegas SuperBook tells Covers. "The best time to bet the favorite is usually as close to the fight as possible. We’ll write more tickets on Maidana, but will take more money on Mayweather."

With Mayweather currently listed in the neighborhood of -725 all the way up to -1,000, is there any value in backing the undefeated champion in Saturday night’s rematch?

"You would need a significant bankroll to overcome 46 losses and that's what you would be sitting on if you kept banking on Mayweather’s opponents year to date," says Oddessa. "It's Floyd or pass. Oscar Wilde said, 'People know the price of everything and the value of nothing.' Crazy things happen, but there's no value in a losing bet. I don't see any value in betting against Floyd."

If backing Mayweather is too rich for the blood and supporting Maidana is foolish, considering the undefeated and undisputed opponent standing across the ring, there’s another option for bettors to explore before making a wager for Saturday night’s title fight.

Six of Mayweather’s last seven fights have reached the cards and resulted in a decision victory. And betting Mayweather by decision doesn’t come with the same lofty price tag as backing the champ simply to win.

"Floyd by decision is the logical outcome and is reasonably betable at ballpark prices of around -250. But you always have to expect the unexpected. I can see Floyd putting Maidana on the canvas, as Victor Ortiz and Amir Khan both did in the past. Maidana gets up, but a decision or technical decision is the most logical outcome."