Cotto vs Martinez odds and preview: Sergio remains the slim favorite as a B-side

At best, Saturday's HBO pay-per-view main event can be viewed as a triumph of matchmaking; an intriguing style clash between two proven, elite, fighters.

At worst, it could be perceived as a money-grab by two thirty-something boxers whose best days are almost certainly now well behind him; a peculiar, discrepant squaring off between an injury-ravaged - albeit lineal - middleweight champion and a man best regarded for his travails at, or just south of, welterweight the best part of a decade ago. In reality, it's probably some combination of the two. What's harder to argue is that Miguel Cotto (38-4, 31 KOs) and Sergio Martinez (51-2-2, 28 KOs) aren't legitimate headliners in their own right, and that two big names coming together for a contest of this stature - even after some protracted negotiations - isn't a good thing for the sport.

There are few more reliable indicators to a can't-miss fight than the questions it raises and, throughout its build-up, Cotto-Martinez has raised more questions than most. What version of Martinez are we going to see on Saturday night? Was that struggle against Martin Murray a one-off, or an undeniable red flag that age and wear and tear have finally caught up with him? What effect, if any, will fighting without a knee brace? Will Cotto simply be giving up too much size? Will Cotto, under the tutelage of Freddie Roach, persist with the body attack that served him so well last time out against Delvin Rodriguez? Will it even be effective against somebody who isn't Delvin Rodriguez?

When the fight was first announced, the oddsmakers sided with the conventional wisdom that Martinez would present a step too far for Cotto, already far from the world's largest light-middleweight, and made the Argentine a touch bigger than a three-to-one favourite (-275) at the leanest, and no bigger than -225, with Cotto a two-to-one (+200) underdog. There's been a bit of jostling across the board since though, but it's been one way - and all the movement's been with the Puerto Rican. It's a viewpoint that has its merits, of course. Cotto is the younger, probably fresher of the two, and is coming off an emphatic stoppage under a coach who appears to know how to play to his man's strengths. In the case of Martinez, those involved early have found plenty of reasons to oppose the champion: surgery, age, and scraping a contentious decision win in a fight he was expected to win much more comfortably are perhaps just three of them.

You suspect, though, that the key to the betting upset tomorrow night lies with Martinez' mobility. It would be a surprise if Cotto's strategy didn't include trying to walk down Martinez to set up that body assault, and if the movement from the champion fails him, then he could be in for a long night. If it doesn't - and it wasn't so long ago that we saw him running rings around Chavez Jr, to name but one - then the entire argument against Martinez not winning this fight, one on the basis of physical breakdown and geriatric failings, could fall rather flat.

There's no consensus in exactly how this fight will be won either - another clear sign of a bout that hinges on ifs, buts, and maybes. Looking first at the upset, it's Cotto by stoppage that's slightly favoured - at best a four-to-one (+400) shot, but available elsewhere at threes. Going by the stats alone, it would appear a reasonable route for those who fancy Cotto to dethrone the titleholder - five of the Puerto Ricans last six wins have ended inside the distance, and all of his last four victories, coinciding with his move to 154lbs. There have, of course, been some high-profile defeats to disrupt that trend - and some questionable opposition in those contests he has prevailed in - but you have to look back nearly five years to find the last time that Cotto had his hand raised after consulting the judge's scorecards. Backing the stoppage is a vote that he handles the size discrepancy without much ado, however, and those who fancy him to get the job done over the full twelve rounds can do so at a best-priced 11/2 (+550), but there's a considerable range of opinions across varying firms here, and the Cotto decision is as short as 7/2 (+350) in places.

The layers have made the decision win for the favourite their most likely outcome, but not overwhelmingly so. Martinez' last two wins have come by way of the cards - the first, over Chavez Jr, snapping a streak of four straight early nights (Williams II, Dzinziruk, Barker, and Macklin) - which mirrors the fact that Cotto's last two defeats have been at the behest of the judges - and a repeat can be backed at a market-best +163, with +140 more widely available. For those who presume Martinez will simply be too big, too strong for Cotto, and that he'll look closer to his devastating best than many anticipate , the 11/4 (+275) that he'll win emphatically inside the twelve will hold plenty of appeal. There's a vote from the bookies that we'll see this go the distance, albeit tight, and it's -137 that we hear the final bell, with Ladbrokes going +125 that proceedings are more abruptly brought to a close.

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