Watch for overachieving understudies

Who’s going to make it to the Super Bowl?

Keep an eye on the over/unders.

That’s the overachieving understudies, and each of the four teams in Sunday’s conference championship games has at least two of them. They are the unheralded players who have ably stepped into key roles to help their teams -- New Orleans, Minnesota, Indianapolis and the New York Jets -- get to this point.

A look at some of the no-names who’ve got game:

Jets

SHONN GREENE, running back: Greene, a rookie from Iowa, expected to spend this season learning behind veterans Leon Washington and Thomas Jones. But when Washington suffered a compound fracture of his right leg in Week 7, the third-round pick was thrust into action.

The Jets didn’t break stride, finishing the regular season with the league’s top-ranked ground game. Greene is a punishing runner who last Sunday broke free for a 53-yard touchdown against San Diego. In the Jets’ two postseason games, he has run for 135 and 128 yards.

His only problem has been hanging on to the football, something that wasn’t an issue in college. He has three fumbles in 108 carries.

SIONE POUHA, nose tackle: Pouha is part of the three-man rotation that has replaced Pro Bowl nose tackle Kris Jenkins in a defense ranked No. 1 against the run. Howard Green and Mike DeVito also log significant time at the spot.

Amazingly, the Jets are actually playing better against the run without the 360-pound Jenkins in the lineup, although no one is questioning his value. In the first six games before Jenkins suffered a season-ending knee injury, the Jets gave up 115.7 yards rushing a game. In the last 10 games of the regular season, that average dropped to 88.4.

Saints

JERMON BUSHROD, left tackle: Bushrod, who stepped into the starting lineup when Pro Bowl left tackle Jammal Brown went down with an injury in Week 2, will face an enormous challenge Sunday. He’ll be the blocker between Minnesota’s Jared Allen -- among the NFL’s premier pass rushers -- and Saints quarterback Drew Brees.

Bushrod, a third-year player slated as a backup, has played surprisingly well this season. He has had some memorable meltdowns, however, including a shaky performance in a loss to Dallas in which he was overwhelmed by the Cowboys’ DeMarcus Ware. Saints Coach Sean Payton conceded after that game that he hadn’t given the young players enough help in the form of extra blockers.

BOBBY McCRAY, defensive end: McCray replaced Charles Grant after the Saints’ longest-tenured player was sidelined by a triceps injury. The results have been mixed. Although McCray has made some plays, he has only 1 1/2 sacks and still has a lot of work to do.

The most memorable of McCray’s moments came in the divisional game against Arizona, when he clobbered an unsuspecting Kurt Warner after an interception, flattening him with a clean but vicious hit.

Colts

MELVIN BULLITT, safety: Indianapolis was fortunate to have Bullitt ready and waiting at midseason after All-Pro safety Bob Sanders went down with elbow and biceps injuries.

An undrafted free agent who signed with the team in 2007, Bullitt had limited action in 2008 yet still intercepted four passes, three of them game-saving picks.

It was Bullitt who made the pivotal tackle on fourth down in a 35-34 victory over New England this season, a play that had the sports world questioning the sanity of Bill Belichick and his choice to go for it instead of punting.

PIERRE GARCON, wide receiver: A little-known receiver drafted in 2008 out of Mount Union College in Ohio, Garcon has done an outstanding job replacing Anthony Gonzalez, who suffered a season-ending knee injury in the opener.

Although Garcon has caught four touchdown passes this season, his biggest play was a defensive one. He chased down Ed Reed last Saturday after the Baltimore safety had intercepted a pass, and stripped the ball from his grasp.

“He took my TD away,” Garcon said. “I had to get it back.”

Vikings

BENNY SAPP, cornerback: Sapp, a backup for four seasons in Kansas City, started for most of the season in place of the injured Antoine Winfield (fractured foot), among the Vikings’ defensive stars.

Sapp told reporters this week that former Chiefs coach Herm Edwards once sat him down and told him he wasn’t good enough to make it in the NFL. Edwards recalls a conversation with Sapp but insists he would never say something so definitive. That’s how Sapp remembers it, at least, and he now uses that memory as inspiration.

JASPER BRINKLEY, linebacker: Brinkley had quite a task stepping in for middle linebacker E.J. Henderson (broken leg), one of the team’s physical and emotional leaders. The Vikings like how Brinkley has played against the run so far but acknowledge he has work to do against the pass.

That makes Sunday’s game a particular challenge for him because Minnesota is facing a quarterback who leads the NFL with an average of 292.5 yards passing a game.

“Never in my wildest dreams would I have thought I’d be in this situation,” Brinkley said. “But now that I’m in, I’ve just got to be able to go with the flow.”

sam.farmer@latimes.com

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