Keith Thurman defeated Robert Guerrero on Saturday to retain his Interim WBA Welterweight Championship.

Thurman improved his overall record to an undefeated 25-0-1 with 21 career knockouts. He didn't knockout Guerrero, but he did win the fight convincingly and was able to knock him down once. Thurman is still just 26 years old, and the future looks bright for "One Time."

So what's next? Here are five possible opponents Thurman could face in 2015 for his next fight:

1. Marcos Maidana

Maidana may have five losses on his portfolio, but he did take Mayweather the distance twice in 2014. The 31-year-old Argentinian is still a household name who Thurman should be able to defeat. Maidana wants a chance at Manny Pacquiao, but that may have to wait after two consecutive losses. A Thurman vs. Maidana fight would be a great chance for Maidana to prove fans he's not yet finished.

2. Loser of Mayweather-Pacquiao

The odds of Thurman facing the winner of Floyd Mayweather-Manny Pacquiao is extremely unlikely. But he can do the next best thing, which is face the loser. The loser will surely want a rematch, but they'll probably have to go through at least boxer first to get that said rematch. If Mayweather loses to Pacquiao, he could prove everyone he still has power by defeating Thurman. If Pacquiao loses, he may have to face Thurman to get back to Mayweather in the future. As for Thurman, he's up for the challenge. He has called out Mayweather numerous times as well as Pacquiao. He wants the opportunity, but will he get it?

3. Juan Manuel Márquez

Juan Manuel Márquez is 41 years old, but he can still pack a powerful punch. His most notable win came against Pacquiao in 2012. Márquez still doesn't have a scheduled fight, and Thurman could be the right opponent. A Thurman vs. Márquez bout would showcase two very similar fighting techniques, except a 15-year age gap. Not many fans realize it, but Márquez is currently the No. 3 ranked Welterweight fighter in the world today. If Thurman can't get a fight with Mayweather or Pacquiao, he can face the next highest boxer, Márquez. Thurman is currently No. 4 in the Welterweight division after his latest victory over Guerrero.

4. Timothy Bradley

After beginning his career 28-0, Timothy Bradley hasn't exactly impressed many over the last two and half years. Bradley hasn't won his last fights, a draw to Diego Gabriel Chaves and a loss to Pacquiao. His "victory" against Pacquiao in 2012 still has fans shaking their heads at judges. Bradley has fallen to No. 9 in the Welterweight rankings. Still, Bradley has great speed, and he's never been knocked out before. Thurman has called out Bradley in the past, but Bradley hasn't accepted any challenges yet.

5. Robert Guerrero

Why not? Thurman vs. Guerrero part one was great, especially considering it was on cable television. Thurman dominated the fight early on scoring huge powerful hits, but Guerrero refused to stay down. Guerrero was knocked down once, while Thurman was never knocked down to the canvas. Guerrero has never been knockout out in his career, and Thurman may just want to show everyone he can do that later this year. Guerrero, on the other hand, may just feel he can beat Thurman in a rematch. Guerrero and Thurman are two of the toughest Welterweight fighters today, so a rematch would be much-watch television.

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