College football’s early story line has been dominated by the sport’s have-nots, including East Carolina of Conference USA, which has notched a pair of upsets over ranked Bowl Championship Series conference teams. This will change Saturday night, though, when no. 5 Ohio State — most likely without its best offensive player, tailback Chris “Beanie” Wells — visits top-ranked USC in the season’s first battle between mega-programs.

No. 5 Ohio State (2-0) at No. 1 USC (1-0)

Saturday, 8 p.m., ABC

Ohio State has played in — and lost, in embarrassing fashion — the last two BCS title games, but some feel this year’s team is better than the last two. USC has been one of the dominant programs of the decade, sharing a national championship in 2003 before claiming the outright title in 2004 and being denied a three-peat by Texas in 2005.

USC’s “falloff” since that stretch consists of two losses in each of the last two seasons to miss out on the national championship game each time. Overall, Pete Carroll’s team has posted six straight 11-plus win campaigns, with five BCS game wins and three Heisman winners along the way.

A track record like that means that USC gains automatic entry into the national-title discussion, and the Trojans did not disappoint in their only game thus far, pasting Virginia, 52-7, two weeks ago. The scariest thing about that result for USC’s opponents was the play of the offense, which was supposed to be rebuilding, with eight new starters this year.

Instead, quarterback Mark Sanchez threw for 338 yards and three scores in his debut as the full-time starter. Sanchez filled in for an injured John David Booty a bit last year, but his starting spot looked to be in jeopardy at various times throughout the fall as he battled Arkansas transfer Mitch Mustain and a knee injury. But against Virginia, Sanchez looked more like recent USC Heisman winners Carson Palmer and Matt Leinart than the player who stumbled in the Trojans’ critical loss at Oregon last season — one of his three starts.

Sanchez showed off a quick release and a beautiful deep ball against Virginia, making USC fans forget that their receivers are supposed to be a weak spot. Damian Williams, Patrick Turner, and Vidal Hazleton continually got open against the Cavaliers, and Sanchez found them a combined 14 times for 186 yards.

The wideouts are sure to be more challenged this week against an Ohio State secondary that features cornerback Malcolm Jenkins, one of the top NFL prospects at his position. Still, Jenkins won’t be able to slow the passing game without a sizable assist from the Buckeyes’ front seven, which must pressure Sanchez and prevent the USC running game from going wild, what with its stable of five-star recruits at tailback. The key player for the Buckeyes is linebacker James Laurinaitis, who must maintain discipline against the run while getting through the relatively green USC offensive line on the occasional blitz.

Though USC does not run the spread offense that has given Ohio State such fits in the last two BCS title games, the Trojans do like to move the pocket for Sanchez, which could similarly break down the Buckeyes’ defense. If that happens, the final score may resemble the one-side results of the past two postseasons.

As if USC’s star-studded defense — with perhaps eight future high NFL draft picks among the starting 11 — needed an assist, it got one Thursday, when Ohio State coach Jim Tressel announced that Wells is “doubtful” for the game. Wells, a preseason Heisman favorite, left the Buckeyes’ season opener with a toe injury and sat out last week. He had hoped to play, but his injury did not respond well after practicing earlier this week.

Not playing against Wells means USC linebackers Brian Cushing and Rey Maualuga have an easier task — they can concentrate on harassing quarterback Todd Boeckman, or perhaps freshman Terrelle Pryor, a run-pass threat who may see more time as the Buckeyes search for a big-play threat to replace Wells. Ohio State certainly missed Wells as it struggled against an Ohio University team it should have overwhelmed last Saturday.

It’s also possible that Ohio State got caught looking ahead to a game its players have been hearing about for months. They certainly wouldn’t be the first group to fall victim — just ask USC. Carroll’s best teams, from 2003-05, played many close games against teams they were expected to dominate. But they usually reserved their best effort for the biggest contests.

Tressel used to have a similar big-game reputation before the BCS disasters. He still has a gaudy 6-1 record against Michigan and can go a long way to silencing his doubters with a win here.

No matter who wins, the stakes could not be higher. To the victor, the path leads to another BCS championship game, while the loser falls into the once-beaten, second-chance bracket — not a place either of these programs expect to be in mid-September.

Mr. Levine is a writer for FootballOutsiders.com.