Please update your flash player...

CompuBox: Rios vs. Chaves

When Manny Pacquiao met Brandon Rios last November, the "Pac Man" -- believe it or not -- had not won a fight in two years and 12 days. Pacquiao responded by producing his best form since pounding Shane Mosley two-and-a-half years before and winning a comprehensive 12-round decision.

When Rios meets Diego Chaves on Saturday, it will have been 22 months since his last victory, his seventh round TKO over Mike Alvarado in the first of their two fights. Will Rios shake off the ghosts as well as Pacquiao did against him? Or will Chaves confirm that Rios is a waning force?

As for Chaves, he had already dealt with the first loss of his career against Keith Thurman 13 months ago by returning to Argentina and cracking Juan Godoy in three rounds. A victory over Rios, which would be his first outside his native land, would put him back in the 147-pound title conversation but a defeat will surely peg him as a regional standout who struck his head on a glass ceiling.

On paper, their aggressive styles seem made for one another. But will that translate inside the ring? Not even they will know until the first bell rings.

Statistical factors that may shape the outcome are available on InsideHBOBoxing.com.

Rios' Struggles: When Rios was at his best -- a few years and 12 pounds ago -- he boasted a rare blend of extreme volume and accuracy. In his lone WBA lightweight title defense against Urbano Antillon he averaged a mind-blowing 107.3 punches per round, landed 50% of his total punches, 42% of his jabs, 56% of his power shots and out-landed the challenger 162-95 overall, 53-18 jabs and 109-77 power in less than three rounds. his 36.3 power connects per round nearly tripled the 13.6 lightweight average. Yes, he took more than his share (44% overall, 33% jabs, 47% power) but his firepower was more than enough to get the job done.

Once his weight struggles kicked in he lost that magic. He was overweight in 135-pound title fights versus John Murray and Richar Abril and his last two fights against Mike Alvarado (fight two) and Pacquiao illustrated the erosion of form. Against Alvarado, he averaged 68.6 punches per round -- still above the 60.0 junior welterweight norm but below his best -- and was out-landed 261-241 overall and 84-59 jabs, negating Rios' 182-177 edge in power connects. Alvarado struck him with 38% of his hooks, crosses and uppercuts while Rios landed 34% of his.

The slide was even more dramatic against Pacquiao. Rios may have been campaigning in a more comfortable weight class -- and he was even heavier once he rehydrated -- but he paid a big price in terms of his form as well as the punishment Pacquiao dished out. Averaging just 41.8 punches per round -- far below his previous career low of 53.2 against Oscar Meza in May 2009 -- Rios was hit often (281-138 overall, 58-25 jabs, 223-113 power) and at a high percentage (36% overall, 48% power). The only bright spot was that he managed to hit Pacquiao with 43% of his power shots but they had no effect on the Filipino. That was telling given that Pacquiao had suffered a one-punch KO loss in his most recent effort and was coming in off the longest layoff of his career.

What does Rios have left in the tank, and will it be enough to repel the bull-strong Argentine?

Volume Equals Victory: Like Rios, Chaves thrives when he gets his engine running. Seventeen of his 19 knockouts have occurred within three rounds and his high output is the main culprit. In blowing out Ismael El Massoudi (TKO 2) he averaged 79.4 punches per round and the trend held during his wins over Jorge Miranda (KO 3, 107.4 per round) and Jose Miranda (TKO 2, 80.2).

When he's forced to go longer distances he has been able to maintain his energetic pace. Against Eduardo Flores (TKO 9) he ranged between 72 and 92 punches per round and his body attack accounted for 109 of his 186 power connects. In beating the sly 38-year-old Omar Weis he fell behind early due to Weis' wiles and a shocking knockdown. But from the eighth round forward Chaves shifted into overdrive and from rounds eight through 11 he out-landed Weis 143-84 (total) and 124-60 (power) en route to a narrow but deserved victory. In all Chaves out-landed Weis 271-226 overall and landed 29% overall and 35% of his power shots while tasting 31% of Weis' total punches and 38% of his power punches.

When he stepped up in class against Thurman, the volume game all but disappeared. He averaged only 49.5 punches per round, well below the 76.5 he averaged in his five other CompuBox-tracked fights, but he managed to give "One Time" everything he wanted -- and some that he didn't want -- for eight rounds before suffering knockdowns in the ninth and 10th rounds. Thurman's success in the final two rounds enabled the American to vault ahead in terms of connects (118-107 overall and 85-68 power) and percentages (29%-24% overall, 16%-15% jabs, 41%-34% power).

Also, Thurman's balanced boxing (202 jabs, 205 power shots) forced Chaves to stray from his power game and engage in a more scientific match in terms of punch selection (255 jabs, 198 power shots, a 56-44 split in favor of jabs that conflicts with the 60-40 split in favor of power shots in his other five CompuBox-tracked fights). But given Rios' past, Chaves won't have to worry about technical boxing; he'll be there to hit -- and be hit.

Prediction: The tag line for Greg Haugen-Ray Mancini was "Tough Guys Don't Dance" and such will also be the case with Rios and Chaves. Both are tough, tenacious battlers who come at opponents in straight lines. Expect plenty of power shots and a high contact fight: 29 of their combined 35 landed punches per round (83%) were power shots.  Opponents landed 43% of their power punches vs. Rios, while Chaves opponents landed 38% of their power shots.  A plus for Rios: He may be a badly faded force but he at least has a far more dependable chin -- and he'll need it. Chaves was floored and nearly knocked senseless against the otherwise light-hitting Weis and was indeed knocked senseless against the ferocious-punching Thurman. However, Rios doesn't have that kind of power and Chaves has less miles on the odometer. Chaves may be 22 days older but he's years younger in terms of ring age. Also, welterweight is not Rios' best weight and defense has never been a strong suit. Chaves by decision in an action fight.

Brandon Rios vs. Diego Chaves

BAD: August 2, 2014 at 9:45 PM ET/PT

Sergey Kovalev vs. Blake Caparello
Jessie Vargas vs. Anton Novikov