Fans of the Filipino boxer Manny "Pacman" Pacquiao have been waiting for someone to truly challenge their champion. Pacman hasn’t lost a fight since 2005, a span of 14 fights that included just one close bout, a 2008 split-decision victory over Juan Manuel Marquez. Pacquiao and Marquez had also faced each other four years earlier, ending in Pacman’s second career draw, thanks in part to a judge’s scoring error. When the two men met for the third time last month, the fight again ended in close, controversial fashion, an indication either of their fierce matchup or the decline of Manny Pacquiao.

When Pacquiao and Marquez first squared off in 2004, the Filipino was still a featherweight and hadn’t begun the march toward higher weight classes that established him as one of the world’s top pound-for-pound fighters. Exhibiting the speed and power that remain his hallmark, Pacman knocked down Marquez three times in the first round, an outcome that would have ended the fight under different rules.

Instead, Marquez was saved by the bell and grew stronger as the fight continued, clearly winning several of the late rounds. After the required 12 rounds, two of the judges scored the fight in favor of each fighter, while the third, Burt Clements, scored it dead even. Although the results stood, Clements later admitted he’d scored the three-knockdown first round incorrectly, and Pacman should have won the fight on his card. Pacquiao also revealed he’d injured his hand in the furious first round, preventing him from continuing his early assault.

This flawed outcome brought added significance to their 2008 rematch, which occurred after both fighters had climbed weight classes. Since their first bout, Pacquiao had fought seven superfeatherweight matches, losing once to Erik Morales (just Pacman’s second career defeat) before defeating Morales in two subsequent rematches. Marquez, on the other hand, fought in the lighter featherweight division for five of his next seven bouts, also losing once, against Indonesian Chris John.

Pacman seemed more comfortable at the higher weight and proved it by dropping Marquez late in the third round, then nearly flooring him again soon after Marquez returned to his feet. But Marquez recovered in the middle rounds, building an advantage over Pacquiao that continued through the end of the fight. The judges awarded Pacquiao a split decision, with the tiebreaking judge giving the fight to Pacman by just a point. Many observers questioned the scoring in the sixth round, which seemed to have been dominated by Marquez, but which two judges had given to Pacman. Controversy reared its head once again.

In the years since that second fight, the two fighters’ careers have continued to diverge. Pacman has vaulted into international prominence, becoming the first fighter to win a title in eight different weight classes. He has dominated internationally known fighters such as Oscar de la Hoya and "Sugar" Shane Mosley, and he scored a dramatic second-round knockout of Ricky Hatton in 2009. Marquez, in the meantime, battled lesser-known fighters or those in decline, like two fights against the once-formidable Juan Diaz. The one exception, Floyd Mayweather, Jr., beat Marquez handily by unanimous decision.

For this reason, commentators saw the ascendant Pacquiao as a clear favorite over the 38-year-old Marquez in their third matchup, and prefight odds were heavily in Pacman’s favor. Reality, however, told a different story. As in their previous meetings, both men dominated different portions of the fight, but this time, Marquez didn’t kiss the canvas, highlighting what some see as Pacquiao’s declining power. The Mexican’s improved durability might have also come from familiarity with Pacman’s fast-and-furious style, in which he attacks from multiple angles with a variety of punches.

Whether it was Marquez’s defense or Pacman’s diminished power, the fight featured some tentative early rounds, unlike their earlier matchups. Pacquiao remained aggressive, however, and Marquez retreated and dodged the onslaught before striking back in the middle of the fight. Building from his counterpunches, Marquez staggered Pacman near the end of the fourth and fifth rounds and opened a cut inside Pacman’s mouth. But Pacquiao redeemed himself with energetic flurries late in several rounds, possibly influencing the scoring of the judges.

Though neither boxer dominated the final rounds, Pacman was more aggressive; this and several more late-round combinations appeared to give him the edge. When the fight went to the scorecards, two of the judges gave Pacquiao the fight, while the third judge scored it dead even. Marquez’s Mexican compatriots at the Las Vegas fight booed their fighter’s defeat, lobbing empty beer bottles into the ring, and Marquez, convinced he had been robbed, stormed off to the dressing room without a word for ringside interviewers.

As postfight emotions cooled, analysts pointed to the Compubox statistics, which gave the edge to Pacman in nearly every category. Many of those who protested the final decision remembered prefight expectations; a final score this close can be seen as a kind of victory for Marquez.

Inevitable discussions arose about a fourth fight between the two fierce rivals, but speculation about Pacquiao’s future loomed much larger. Although the superfight against Floyd Mayweather, Jr. has yet to come together, ESPN’s Kieran Mulvaney pointed out that Pacman’s lack of dominance in this latest bout has taken some of the luster — and payday — away from that matchup. Whomever the multi-weight Filipino sensation takes on next, everyone will be watching to see if he can regain his once-spectacular form, or if he is indeed a great fighter in decline.