SOUTH BEND – It's probably more about small sample size and soft competition than it is about seismic improvement.

But the statistical jab Notre Dame head football coach Brian Kelly must deal with this week is facing a team, Michigan State (2-0), Saturday night on the road that checks in as the No. 2 pass-efficiency defense in the entire 129-team FBS.

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Up from No. 84 last season.

Reality probably lies somewhere in between. Getting junior quarterback Brandon Wimbush to expose that and help bring better balance to ND's suddenly run-reliant offense is the challenge, and one that no one saw coming from the first-year starter.

Kickoff at Spartan Stadium is 8 p.m. EDT between two unranked teams that tangled as ranked opponents last season, then proceeded to combine for 17 losses. FOX has the telecast.

"We don't have to throw for 300 yards, but we've got to hit receivers," Kelly said Sunday, a day after his Irish (2-1) pummeled host Boston College, 49-20, with the most prolific Irish running attack (515 yards) since a 1969 rout of Navy and the best per-carry average (10.1) in the school's modern-day history.

"Receivers have got to make some tough catches," he said, "and we've got to put Brandon in a position where we're featuring the things that he does well."

Schematically, Michigan State will likely funnel its defense Saturday night to force the issue.

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So the question is how does Kelly get there, where passing is as much in Wimbush's comfort zone as running the ball appears to be?

The starting point – or rather re-starting point – is a national ranking of 114th in passing offense and 124th in passing efficiency.

Bowling Green and Western Michigan, incidentally, the two teams the Spartans defeated before a bye week last weekend, are living in the same neighborhood when it comes to team pass efficiency, 123rd and 120th, respectively.

Kelly believes Wimbush (11-of-24 for 96 yards, 1 interception on Saturday) is too good to take up a permanent residence there. Wimbush's past would suggest that as well.

He has a history of being a quick learner, a history of making leaps-and-bounds improvement – so much so the Irish passed on him as a high school junior in their recruiting evaluations and deemed him a must-have as a senior at St. Peter's Prep in Jersey City, N.J.

Based on his arm, not his feet.

His 10.85-second speed in the 100-meter dash was a trump card, not a calling card. And Wimbush fancied himself as a pocket passer. He didn't study the nuances of being a true dual threat until he arrived at Notre Dame.

There were no real hints last spring and in fall training camp that his passing game wasn't still ahead of his running.

Instead he's been a September revelation in the latter area and a remedial student in the former. It's what Wimbush is seeing from defenses that's causing hiccups in his mechanics, Kelly explained.

"The processing has just got to be a little bit quicker," Kelly said. "He's seeing it, but it's a little bit late ... which forces him to rush things and overthrow a little bit.

"He threw a beautiful corner route to Durham Smythe, because he loves that route, so it came out of his hand beautifully. He was positioned great in the pocket.

"And so when he sees things and he's confident and he knows them, he's synced up and he syncs up our offense wonderfully. We've just got to get him to that (consistently). And when we do, I think we've got great balance."

But it's not just about the quarterback.

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Georgia's speed exposed ND's offensive line in a 20-19 Irish loss on Sept. 9. And the Irish made countermoves for BC. In terms of the pass protection, the litmus test was Eagles senior defensive end Harold Landry, the 2016 national statistical champ in both sacks (16.5) and forced fumbles (7).

The Irish made him statistically and schematically irrelevant (1 tackle, 0 sacks) on Saturday, for the first time since the final game of his freshman year, when a brief cameo in a Pinstripe Bowl loss to Penn State (31-30 in OT) netted him zero tackles.

From a wide receiver standpoint, Kelly shortened the wide receiver rotation last week, elevated one of his high-ceiling prospects – sophomore Chase Claypool – to a larger role, and ditched versatility for specialization, so the receivers could be more precise and consistent.

Statistically, it didn't pay dividends Saturday (3 catches for 11 yards among the wideouts), but Kelly is convinced it will eventually.

"He's big, he's physical, he's got speed," Kelly said of the 6-foot-4, 228-pound Claypool. "We just think that he needs to continue to grow at that position.

"We just like that he blocked very well for us. He was assignment-correct. We saw him really grow in the areas that we wanted him to grow in."

As a consequence of the smaller rotation philosophy, sophomore Javon McKinley is being strongly considered for a redshirt season, Kelly said Sunday.

McKinley, the highest-rated of ND's 11 receivers coming out of high school, has not played in a game this season after his freshman year ended late last October with a broken leg.

"We didn't get enough out of his year last year, so I try to save a year under those circumstances for those guys," Kelly said. "If they're still growing, still learning, I don't want to accelerate them through the program unless they are squared away in terms of all of your traits."

ND's leading receiver at the moment is a tight end, junior Alizé Mack (9 for 101). Its second-leading receiver is a running back, junior Josh Adams (8 for 69).

The tight end corps, in fact, has 15 receptions – three more than they had all of last season – and are on a trajectory to rival the highest total by that position group in the 2000s (66 in 2011).

Even the most dominant Irish wide receiver from 2016, junior Equanimeous St. Brown, is trying to find traction (7 catches, 99 yards, 1 TD).

"In terms of all the (wide) receivers, they just have to make more plays for us – contested catches – and they will," Kelly said. "Hasn't got off to the kind of start we want, but it's a long season, and I have a great deal of confidence in them."

That's not to say being the nation's fifth-ranked rushing team is toxic to team success. Adams stands No. 8 nationally in rushing yards per game (147.7) after the fourth-most prolific rushing performance in school history (229 yards on 18 carries), on Saturday.

He trails only LSU's Derrius Guice in career yards per carry (7.3 to 6.7) among career active players.

Wimbush, meanwhile is 26th overall in rushing yards per game (104.7), fourth among quarterbacks and first among QBs that don't run a triple-option offense. He's averaging 6.4 per-carry and has six rushing TDs.

That's the second most rushing TDs in the FBS this season regardless of position, and four short of DeShone Kizer's single-season record by an Irish QB, with at least nine games still to play.

Wimbush's 207 yards on 21 carries against the Eagles obliterated Bill Etter's 48-year-old, single-game rushing mark by an ND QB. The 21 carries part of that sentence, though, could be a concern long term.

Wimbush is averaging 16.3 carries a game in his first three starts, with the number climbing each week. That would project to 212 carries over a 13-game season.

Another benefit of ND's retro look in the run game is a 15-of-15 success in the red zone, tied for the nation's best. Thirteen of the 15 red-zone scores have been TDs.

The highest the Irish have ranked at season's end in red-zone offense under Kelly is 49th, in his first season (2010). They haven't been higher than 70th since.

But the Georgia game is a reminder that the ability to balance an offense is necessary when facing an elite defense. Of the teams remaining on the Irish schedule, first-year defensive coordinator Mike Elko's old Wake Forest team (3-0) is the one that most convincingly projects that kind of prowess this early.

Then again, small sample sizes can lead to statistical mirages. Kelly is banking his passing game turns out to be one of those.

This article is written by Eric Hansen from South Bend Tribune, Ind. and was legally licensed via the Tribune Content Agency through the NewsCred publisher network. Please direct all licensing questions to legal@newscred.com.