Final Examination: Amir Khan vs. Marcos Maidana, Victor Ortiz vs. Lamont Peterson

Michael Nelson previews tonight's HBO 140lb doubleheader.

Two reclamation projects will endure a final exam tonight at the Mandalay Bay in Las Vegas.

Since being knocked out within the first round against Brendis Prescott, Amir Khan has looked dominant while cautiously match against men who aren't known for their knockout prowess. Tonight, he'll be across the ring from Marcos Maidana, arguably the biggest puncher at 140 pounds.

Maidana, of course, handed Victor Ortiz his only setback a year and a half ago, coming off the canvas to beat the Oxnard, California resident into submission. Ortiz has since been moved gingerly. Nate Campbell was someone thought to be lively enough to test the young man's resolve, but instead moved around the ring with lead in his legs (he retired after a recent loss to Walter Estrada). Tonight, Ortiz is facing someone young, skilled, and desperate; a body punching specialist who moves forward undeterred.

Even with legs anchored down by Father Time, Nate Campbell's molasses pressure made Ortiz look uncomfortable. To Victor's credit, he notched a lopsided decision, but had to be warned several times for holding by referee Earl Brown in the process.

Fight-ending power remains starch within Ortiz' punch though, and Peterson was stunned on three different occasions by Timothy Bradley, who hasn't recorded a KO in over three years. Bradley's stinging right hands have wobbled opponents with stern whiskers before, but Ortiz is twice the finisher Timothy is, so Peterson would be best served to stay off of wobbly legs. The unrelenting style displayed against Bradley may have dire consequences this time around.

If not a granite chin, Peterson does display a body punching pedigree that Ortiz has yet to see in his young career. An uppercut dug into the sternum followed by a left hook underneath the rib cage would make some of those questions he failed to answer against Maidana swirl inside his head once again.

We know that Peterson's heart is fully entrenched in boxing. We're about to find out, for the second time, what happens when the truth serum inside the gloves of a hungry fighter enters the bloodstream of young Ortiz.

Like Ortiz, Amir Khan has been operating under the dark cloud of a shocking knockout loss. While accomplishing plenty under that cloud, he has yet to defeat the type of opponent that will make the storm of questions about his chin dissipate.

Maidana is that opponent. And as a longstanding mandatory for Khan's WBA title, he has been barking loudly for well over a year.

The Argentinian slugger's shine has been dimmed a bit by his struggles against shopworn Demarcus Corley in August. A hard-hitting, top tier Jr. Welterweight should dispose of Corley within five rounds, it was thought. The determined southpaw had other plans, treading turbulent waters to win most of the late rounds.

Maybe Marcos overlooked Corley, or maybe Corley presented a sticky style he had trouble solving. A fleet-footed, long opponent with blurring speed doesn't figure to be an easier puzzle. But it's one that has been in the forefront of his mind since his resounding introduction as a credible threat last year, so any shortcuts he may have taken while preparing for Corley have likely been eliminated for Khan.

Under Freddie Roach's tutelage, Khan has not only looked more polished than he did early in his career, he appears to have sturdier legs when he does get touched in the chin. If Marcos manages to plant an overhand right flush on those whiskers, we'll have the pleasure of seeing how sturdy those legs really are. In between the haymakers, Khan will enjoy sizable advantages in speed, length, and acumen, with enough power to make Maidana think twice about reckless abandon.

But ask their common opponent, Andriy Kotelnik, if Maidana has enough talent to connect on a superb technician. While Kotelnik survived Maidana's onslaught to win a tight decision, his disfigured face told the story of a man who went through pain he had never had to endure inside a boxing ring before.

What happens when Amir Khan goes through something similar? Under the hot lights of Vegas, a definitive test awaits.

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