If Johnny Manziel is a football explosion waiting to happen on the field, Patrick Lewis is the fuse.

Manziel, Texas A&M’s “Johnny Football,’’ is the linchpin of what is the SEC’s far-and-away most formidable offense, one that has overwhelmed most of the defenses the Aggies went against this season.

But without Lewis — the center who “targets’’ opposing defenses, watches for scheme changes and at the same time is expected after every play to beat the referee to the ball — Aggies coach Kevin Sumlin said A&M’s up-tempo offense might not be quite as proficient.

“We can’t do anything until the center gets the ball,’’ Sumlin said. “If we’re all running to the ball and we have no center there, it makes no sense.’’

Lewis, who played at East St. John, has been there without fail throughout the Aggies’ nine games — and is a major component of the unit — one that presents a huge hurdle to Alabama on Saturday in the biggest Southeastern Conference game of the weekend.

Manziel, Lewis & Co. are the last thing Bama and Nick Saban, who expressed his disdain for no-huddle offenses earlier this year after playing Ole Miss, asking rhetorically, “Is this what we want football to become?’’

When No. 15-ranked A&M (7-2, 4-3 SEC) plays at Bryant-Denny Stadium in Tuscaloosa, Ala., Alabama (9-0, 6-0) can wrap up the SEC West title or A&M can deal a crippling blow to the Tide’s chances for a third national championship in the last four years.

Consider: The A&M offense averages 44.6 points per game, while the Bama defense gives up an average of 9.1; the Aggies offense runs up an average of 559.5 yards per game, and the Tide surrenders an average of 228.8; the A&M offense (and this comparison could be telling) runs an average of 72 plays per game, whereas the Alabama offense runs an average of 60.

In fact, LSU may have provided a blueprint in how to beat the Tide by running 85 plays from scrimmage to the Alabama’s 52 last week, when the weary Tide used a blown coverage assignment to pull out a 21-17 victory.

A similar type of game with that many more plays by the opponent could be critical to Alabama. And there’s more: Containing Manziel is far more easier said than done: Second in the nation in total offense with 3,449 yards, Manziel leads the SEC in rushing (1,058 yards) and is second in passing (2,527 yards). Through nine games, with opposing defenses seemingly trying to tackle air, Manziel has been, Lewis said, “really a thing of magic.’’

It should be noted, however, that both Florida (20-17) and LSU (24-19), two teams that approximate Alabama, represent Texas A&M’s two defeats.

It’s one of those accidents of life that Lewis, a 6-foot-2, 312-pound senior, finds himself smack in the middle of a clash of contrasting football teams in a huge Southeastern Conference game.

Playing at East St. John, Lewis was a three-time All-State player — at guard, the position he played his first two seasons at A&M.

Despite his accomplishments, Lewis was not heavily recruited, saying he was courted only by Southern Miss, Tulsa, A&M and, at the very end, Auburn. He would have liked to have played in the SEC when he came out of high school but said he went with A&M because the Aggies were the first major conference program to offer him a grant-in-aid, and he felt a loyalty to them.

So, then, what happened?

Three things.

One, a year ago he was asked to switch positions. He said the transition was difficult.

“What I liked about guard is, I could see the field more, and it was easier to concentrate on blocking assignments,” Lewis said. “At center, making a smooth snap then going to blocking assignments is a little harder.

“I worked on it, though, and I’ve grown to love the position.’’

Two, Aggies coach Mike Sherman was fired after last season, and Sumlin and his hurry-up offense — increasing responsibilities on his center — was brought in.

Three, Texas A&M left the Big 12 Conference and was admitted to the SEC, where they have made a dent, and are now one of the top teams in the West.

“It’s been quite a trip, when you think about it,’’ Lewis understated.

The difference between the Big 12 and the SEC, he said, isn’t so apparent on first glance.

“There are great athletes everywhere major-college football is played,’’ Lewis said. “The difference in the SEC is not only in quality but in depth.

“Teams run people in and out, and there’s very little dropoff in talent.

“You don’t go a week in the SEC where you don’t see some unknown player and think, ‘That guy’s going to be a big name soon.’ ”

There’s something else.

“I love the emotion and crazy fans in the SEC,” Lewis said. “That makes a difference.’’

For all A&M’s offensive assets, Lewis said he doesn’t for a second think the Aggies won’t have to play their best game, plus perhaps get a break or two. Saturday at Alabama.

“They are awesome,” he said. “You look at film and see great athletes everywhere. Alabama is like a machine. But I think — I hope — we can give them a game.’’

Whatever A&M does, it will all start with him — the fuse of the Aggies offense.