SOUTH BEND, Ind. — Three games into the 2018 season, it seemed only a matter of time before Notre Dame's luck would run out. While the Fighting Irish managed a 3-0 start, the issues of the Brandon Wimbush-led offense created too much doubt for comfort.

It turns out the solution to those problems was watching from the sideline all along.

After not throwing a pass in Notre Dame's first two games and only three in No. 3, Ian Book has engineered an impressive surge from the once-lackluster scoring attack. Saturday, the junior quarterback tossed four touchdowns during the Irish's 38-17 triumph over the No. 7 Stanford Cardinal at Notre Dame Stadium.

Though two weeks is not a huge sample, he's brought a clear spark to the scoring attack—one that is reshaping perceptions about the program's ceiling in 2018.

Sure, Notre Dame often receives considerable hype during the offseason. That's not always merited, but Brian Kelly's team at least had an experienced defense as a foundation. The big unknown was whether the Irish had a College Football Playoff-worthy quarterback.

Following one-possession victories over Michigan, Ball State and Vanderbilt, the answer appeared to be a resounding no. Book, however, has quickly turned Notre Dame into a real CFP threat.

During his two starts, Notre Dame has tallied 94 points, a 50 percent third-down conversion rate and one turnover compared to 70 points, a 36.4 third-down clip and four giveaways in Wimbush's three.

In Week 4, the Irish cruised to a 56-27 victory over Wake Forest behind a career performance from Book, who amassed 368 yards of total offense and accounted for five touchdowns.

His hot streak continued Saturday opposite Stanford when he collected 325 total yards. Book's final passing line read 24-of-33 with four touchdowns and zero interceptions. And you could count his bad decisions and poor passes on one hand.

Well, one finger, really.

Of Book's nine incompletions, there were three well-defended passes, two proper throwaways, two drops, a tough back-shoulder ball and an errant downfield shot. That's it.

Additionally, the Irish haven't sacrificed mobility in going from Wimbush to Book—and the latter has been scrambling with purpose.

"What I liked the most about Book tonight," said Kelly after the win, "was if it didn't look right to him he didn't enter into that picture; he got out of it. And he got out of it with his feet."

Stanford played excellent coverage on several snaps that Book still turned into a win for Notre Dame. He picked up 31 yards on four scrambles and evaded three sacks, per B/R tracking, also setting up several conversions by extending plays with his legs.

The most impactful moment was the touchdown pass to Chase Claypool to help the Irish to a 21-14 lead at halftime.

Later in the game, Book bought time for a 3rd-and-9 conversion on a drive that would result in a field goal. His pocket presence and awareness of when to scramble were impressive, and those traits can translate against any competition.

So should his evident timing with Miles Boykin, who gathered career-high marks of 11 catches and 144 yards. The duo connected on sideline routes—back-shoulder balls, curls and outs—with excellent timing and in multiple clutch situations.

Critically, despite that rapport, no pass to Boykin was truly forced. Book had a clear go-to receiver yet didn't overuse him.

"Our chemistry is coming along," Book said. "I love throwing to him."

Future opponents will know Book wants to target Boykin, but disrupting their rhythm will be difficult. Granted, it's true Stanford's defense isn't a top-tier unit. The front seven doesn't create pressure like several of Notre Dame's remaining opponents, let alone an Alabama or Clemson or Georgia potentially waiting in the College Football Playoff.

The Cardinal ranked 90th in yards allowed per snap last year and entered Saturday ranked 49th. While there are talented players on the defense, nobody should be mistaking it for elite.

Conversely, Notre Dame arrived 18th in the category at 4.5 yards per play and held Stanford to the same. The defense consistently generated pressure with four players—highlighted by four sacks and two hurries from Jerry Tillery—and limited Bryce Love to 34 yards on the 16 carries beyond his outlier 39-yard touchdown.

Carlos Osorio/Associated Press

That defense is capable of frustrating any remaining opponent, though Kelly knows the Irish cannot afford to look too far ahead.

"We've got a long season ahead of us," he said. "So if we're going to walk out of here thinking that we just are the best team, we're going to get beat and it's going to diminish this victory."

It's far too early to declare Notre Dame a legitimate threat to hoist the national championship trophy. The schedule is favorable enough that the Irish might not encounter a top-25 opponent, but they won't breeze through a trip to Virginia Tech and a November filled with Northwestern, Florida State, Syracuse and USC, either.

Plus, the gap between Alabama and anyone is currently a chasm. Declaring anyone other than the Tide the favorite is foolish right now.

Nevertheless, an 11-1 finish for Notre Dame is realistic. An undefeated regular season is within the realm of possibility. The Irish are still working toward joining the ranks of true title contenders, but one thing is becoming abundantly clear:

This conversation isn't happening without Book.

Stats from NCAA.com, cfbstats.com or B/R research. Quotes obtained firsthand unless otherwise noted. Follow Bleacher Report CFB Writer David Kenyon on Twitter @Kenyon19_BR.