The Carolina Panthers have invested $89 million on tailbacks DeAngelo Williams and Jonathan Stewart and fullback Mike Tolbert.

I ask coach Ron Rivera if their work in Carolina’s 35-27 victory Sunday against New Orleans is the reason for that investment.

He says it is.

“That’s what we have the ability to do, and we’ve just got to continue to refine it, continue to use our weapons and use them smartly,” Rivera said Monday.

I like trick plays and options, the 6-foot-5 quarterback running 40 yards through the line and down the sideline. Quarterback Cam Newton would add 31 rushing yards to his 40-yard run Sunday and lead the Panthers with 71 yards on the ground.

I love Newton’s long passes to Steve Smith. As the ball moves downfield fans move forward in their seats the way they do at the ballpark when a hitter goes deep.

But there’s something reassuring about the work of the backs against New Orleans. Williams averaged 4.9 yards a carry and Stewart 4.6. Fullback/tailback/H-back Mike Tolbert grabbed a short pass, adeptly changed directions and picked up 20 yards.

I’d love to train my binoculars on Tolbert for a game. He picks up the blitz, slips out for passes and, after his 3-yard touchdown run Sunday, danced a dance that looked like something previously unknown to mankind.

“With Tolbert you get the power guy, that rumbler,” Rivera says. “But he has enough quickness to get outside when he needs to … He’s also really good at protection, really good out of the backfield at receiver.”

Tolbert, 26, is a bargain; he signed a four-year, $10 million contract in March, with $4.2 million guaranteed.

Williams signed a five-year, $43 million contract in 2011; $21 million is guaranteed.

Stewart signed a five-year, $36 million extension last month, with $23 million guaranteed.

I think I would have paid Williams and Stewart what the Panthers did. And I apologize for writing the previous sentence. In sports, you’re supposed to know. It was good or bad, right or wrong, and if you disagree you’re a moron.

For the $36 million the Panthers paid Stewart they could have signed a tremendous pass-rusher, cover corner, wide receiver or offensive lineman.

But the expense attests to a philosophy. Reward the draft picks who perform.

Williams and Stewart prolong each other’s careers. They take turns and don’t complain because they aren’t the featured back. They’re DeJonathan, and when they’re effective so is their team.

Williams is 29 years old, Stewart 25.

Williams carried 14 times Sunday, Stewart 11.

Williams didn’t catch a pass. Stewart caught one for 17 yards.

Williams generated 69 yards, Stewart 68.

The Panthers will play the New York Giants on Thursday. How do the Panthers negate New York’s pass rush, which has only four sacks this season but is among the league’s best?

Get the ball to the backs.

“You look at what Jonathan brings to us (and) that’s an inside presence between the tackles,” says Rivera. Run inside, and the defense has “to tighten up a little bit. They’ve got to try and play those inside gaps a little more, and now you get the edges a little bit easier.”

When Williams is effective outside, the defense has to spread out, which creates openings inside. Both backs, of course, can go inside and out.

Carolina goes as Newton goes. If he’s off, the Panthers struggle.

But here’s a statistic worth considering.

The Panthers have won seven games the past two seasons. They’ve rushed for more yards than their opponents in six of them.