Will Penn State running back Saquon Barkley be taken in the top five of an NFL draft that is dominated by talk of quarterbacks? (John McDonnell/The Washington Post)

There are some non-quarterbacks available in this NFL draft.

Who knew?

It will be, pretty much, all about the quarterbacks when the NFL draft begins Thursday night. Quarterback-needy teams are lined up at the top of the first-round draft order with the Cleveland Browns, New York Giants, New York Jets and Denver Broncos. Other teams could trade up. There is a highly regarded draft class of quarterbacks that includes USC’s Sam Darnold, Wyoming’s Josh Allen, UCLA’s Josh Rosen, Oklahoma’s Baker Mayfield and Louisville’s Lamar Jackson.

The pre-draft talk has been about the quarterbacks. The Jets made a blockbuster trade to move up, presumably for a quarterback. The draft-night focus will be on the quarterbacks. And rightfully so, given the importance of getting the right player at the sport’s most important position.

And yet, there is more to this draft than the quarterbacks. And that begins, some within the sport say, with Penn State running back Saquon Barkley, N.C. State pass rusher Bradley Chubb and Notre Dame guard Quenton Nelson.

“Nelson, Barkley and Chubb are the three best football players in the draft,” said an executive with one NFL team. “The quarterbacks get pushed up. But those guys are the best players, no question.”

Part of the draft-night intrigue will be to see where Barkley, Chubb and Nelson fit in amid all the quarterback madness, which could become even crazier if teams such as the Buffalo Bills and New England Patriots seek to trade up.

The Browns have the first and fourth overall selections. So they could, in theory, take Barkley or Chubb at No. 1 and wait until No. 4 to address their quarterback need. It’s not considered likely, but there’s always the never-say-never chance. If they do take a quarterback first, the Browns would be in line for a non-quarterback at fourth.

The Giants, with the No. 2 choice, could opt against taking a quarterback to serve as Eli Manning’s eventual successor, and instead could add Barkley to give Manning a productive runner or Chubb to replace just-traded pass rusher Jason Pierre-Paul. The Indianapolis Colts, after moving down three spots in the big trade with the Jets, are the draft’s first obvious non-quarterback team at No. 6.

A pass rusher like Chubb plays a position traditionally given a high value in the draft. Things are more complicated with a running back like Barkley and a guard like Nelson. It is only in the last few years that NFL teams have considered it worthwhile again to use a lofty first-round choice on a running back. The success of Todd Gurley with the Los Angeles Rams, Ezekiel Elliott with the Dallas Cowboys and Leonard Fournette with the Jacksonville Jaguars after they were top-10 selections works in Barkley’s favor.

“I think this is a really good draft for running backs,” Browns General Manager John Dorsey said at the NFL scouting combine. “I think there are some really talented running backs in this thing. And that’s not to say whoever the first running back is taken can’t be a franchise difference-maker. … If he’s a good football player and he plays the running back position, I’d love to have him on my team.”

The issue, of course, is whether Barkley will be a game-changing player in the NFL as Gurley, Elliott and Fournette have been.

“I can’t see the future and I can’t sit here and say I’m gonna rush for this amount of yards and I’m gonna have this amount of touchdowns,” Barkley said at the combine. “I don’t know. That’s all God’s plan and what He has for me. What I do know is that I’m going to come to a team and I’m going to work. I’m going to work and that’s something that I’ve been doing since my sophomore, junior year of high school, working and pushing myself and pushing others and pushing my teammates. I’ll continue to try to be a leader and be a competitor. At the end of the day, if I’m able to do all those things, the rest will take care of itself.”

The counter-argument is that productive runners generally can be found in the draft’s middle rounds. Chris Ballard, the Colts’ general manager, said at the combine that he believes there are excellent high-end running backs in this draft, and also good runners to be gotten in the third and fourth rounds.

“There’s a lot of depth at both the offensive line and running back,” Ballard said.

In Nelson’s case, guards generally are not regarded as prospective top-10 picks. But Nelson is considered so good that he is likely to break that trend. The Cowboys, remember, have not regretted passing on quarterback Johnny Manziel with the 16th overall selection in 2014 to take Zack Martin, already a four-time Pro Bowl selection at guard and a cornerstone of their offensive line.

Some observers expect five or six quarterbacks to be taken in the opening round Thursday. An early run on quarterbacks could make quarterback-starved teams even more desperate than usual, and much of the quarterback activity could take place in the first half of the opening round. The more quarterbacks that are taken early, the more that top players at other positions will get pushed down. A couple of those players could be pushed out of the first round entirely.

General Manager Brandon Beane said at the Bills’ pre-draft news conference that it could be a successful draft for the team even if it doesn’t use an early pick on a prospective franchise quarterback.

“There’s a lot of good players in this draft and that was the big thing from moving from [No.] 21 to 12,” Beane said of an earlier trade with the Cincinnati Bengals. “The natural assumption — I get it — is: ‘They’re moving up to get a quarterback, yada-yada.’ No, we improved our draft position. … We’re excited about where that moves us on our draft board, the players that we see would be available there.”

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