Injuries happen, more often to some than others.

They’ve happened a lot to Carson Wentz the last four years. A fractured wrist his last year at North Dakota State. A hairline fracture of his ribs his rookie year with the Eagles. A torn ACL in 2017. A broken vertebra in his back last season.

That’s a lot of bad luck. That’s a lot of missed time. Since 2015, his teams have played 68 games. Wentz has missed 21 of them, including all five of the Eagles’ playoff games the last two years.

He has worked hard this offseason to try to improve his chances of staying healthy. He has attempted to transform his body, changing what he eats and drinks, getting more rest, altering his training regimen.

Will it work? Will it enable him to answer the bell for all 16 games this season and let him make the first playoff appearance of his career?

We’ll see. If it does, the Eagles have a good chance of making another Super Bowl run. Wentz, as he showed two years ago before his knee injury, is that good.

If it doesn’t, well, the Eagles’ fate will be in the hands of Wentz’s inexperienced likely backup, Nate Sudfeld.

Nick Foles stepped in for Wentz two years ago, when Wentz shredded his knee on that dive into the end zone against the Rams. He responded with a performance for the ages, leading the Eagles to three playoffs wins and a dramatic Super Bowl victory over Tom Brady and the Patriots.

He stepped in again last year after Wentz was shut down with the back injury with three games left in the regular season, and nearly got them to the NFC championship game.

But Foles is gone. He signed a four-year, $88 million contract with the Jacksonville Jaguars in March, That leaves Sudfeld, a fourth-year player who has appeared in just three regular-season games, as the likely Plan B if something happens again to Wentz.

The Eagles will open training camp Thursday with four quarterbacks: Wentz, Sudfeld, Cody Kessler, and fifth-round rookie Clayton Thorson.

Kessler, a 2016 third-round pick of the Cleveland Browns, was signed by the Eagles in mid-May. He has 12 career starts, including eight as a rookie with the Browns.

He didn’t get many reps in spring OTAs because he was still learning the Eagles’ offense. But when he was on the field, he didn’t do anything that made you say, “Hey, he might just wrestle the No. 2 job away from Sudfeld this summer.’’ Maybe that changes over the next few weeks. Probably not.

In all likelihood, when the Eagles open the season against Washington on Sept. 9, Sudfeld will be backing up Wentz.

Sudfeld, a 2016 sixth-round pick of the Redskins, has been with the Eagles since September 2017, when he was signed to their practice squad after Washington released him.

When Wentz was healthy the last two years, Sudfeld was the third quarterback. When he wasn’t, including the last two postseasons, he backed up Foles. So, being a heartbeat away from starting isn’t totally foreign to him.

Something to prove

Nate Sudfeld has a tough act to follow after Nick Foles' all but typical run as the Eagles' backup quarterback.
TIM TAI / Staff Photographer
Nate Sudfeld has a tough act to follow after Nick Foles' all but typical run as the Eagles' backup quarterback.

Sudfeld is a big guy – 6-6 and 227 pounds – with a strong arm and good pocket mobility, and he has an excellent grasp of Doug Pederson’s offense.

But he’s lean on experience. He has thrown just 25 regular-season passes. Twenty-three of them came two years ago in a meaningless Week 17 loss to Dallas right before the playoffs.

Sudfeld completed 19 of those 23 passes that day, but it was a lot of dinking and dunking. Sixteen of his 23 attempts traveled 5 yards or fewer, including five behind the line of scrimmage.

“I’m very confident in Nate,’’ Pederson said a few weeks ago. “I like what he did in the spring. He’s taken another step in his growth with our offense, with our team.

“Training camp’s going to be another step for him. He and I have had some really good conversations, and I think he benefited a lot from watching Nick play, watching him handle the backup role and come off the bench and deal with Carson.

“He’s had a pretty good seat for the last couple of years. Now it’s time for him to really take that next step.’’

Foles wasn’t your typical backup. Unlike Sudfeld, he had a relatively thick NFL portfolio when he returned to the Eagles in March 2017, two years after his out-of-the-blue trade to the Rams by Chip Kelly.

He had made 36 career starts, including 24 during his first go-round with the Eagles. He had 1,285 career pass attempts and 56 touchdown passes.

Hell, the guy led the league in passing in 2013. He was the Pro Bowl MVP that season. He tied an NFL record with seven touchdown passes in one game. His cleats are in Canton.

He had been there. He had done that.

Big shoes to fill

Nate Sudfeld has shown confidence and accuracy in practice, but he hasn't had the chance yet to show if that can translate to games.
TIM TAI / Staff Photographer
Nate Sudfeld has shown confidence and accuracy in practice, but he hasn't had the chance yet to show if that can translate to games.

Sudfeld looks the part in practice. Confident. Decisive. Throws crisp, accurate passes. He’s been there, but he hasn’t done that.

Yet.

He has watched and learned from Wentz and Foles and his coaches. He has tried to make the most of his reps in spring OTAs and in the summer preseason games.

But can the Eagles win with him if something happens again to Wentz? We’ll all find that out together.

His teammates seem to have confidence in Sudfeld.

“We love what we’ve seen out of Nate the last couple of years,’’ tight end Zach Ertz said. “The way that he approaches every day on the practice field and has played on the practice field has given guys a lot of confidence in his ability.

“Practice obviously is completely different than seeing him in game action. If he had to play, there would be a little bit of an adjustment period, just like there was with Nick two years ago. But no one has any doubt about him. He can get it done.’’

Given Wentz’s injury history, it will be interesting to see if Pederson gives Sudfeld a few more reps with the first team in training camp this summer than backups typically get. Same with the preseason.

“Obviously, Carson isn’t going to play every snap in the preseason,’’ Ertz said. “I’m sure there is going to be some overlap with us [first-team players] and Nate in the preseason when Carson is out.’’

“The preseason is as close as we can get to a [regular-season] game atmosphere [with Sudfeld],’’ said quarterbacks coach Press Taylor. “We just need him to continue to work through that and prove he can run the offense and protect the football and lead the offense the way we would like.’’

No respect

Nate Sudfeld completed his first NFL touchdown pass in last season's Week 17 shutout of Washington.
TIM TAI / Staff Photographer
Nate Sudfeld completed his first NFL touchdown pass in last season's Week 17 shutout of Washington.

Sudfeld threw for 3,573 yards, 27 touchdowns, and just seven interceptions as a senior at Indiana. Despite the impressive stats and impressive arm strength and impressive size, though, he was just the 11th quarterback taken in the 2016 draft, behind Kessler and fellow Big 10 signal-callers Connor Cook (Michigan State, fourth round) and Cardale Jones (Ohio State, fourth round).

“My first year in the league, I was the [third quarterback],’’ Sudfeld said. “So I was inactive on game day. You try to stay involved as much as you can. But it’s not the same as when you’re the No. 2 and dressed and one play away.

“I got an opportunity to do that during the Super Bowl season. I backed up for sevenish games, and then eight or nine games last year.

“So it’s been good to get that experience. But there’s not a perfect formula for backing up. You just have to be ready. Nobody cares that you didn’t get any reps with the [first team] all week. You just have to go in and perform.’’

Sudfeld made brief appearances in the Eagles’ final two regular-season games last year. He came off the bench for one snap late in their dramatic 32-30 Week 16 win over Houston after Foles took a lick from Jadeveon Clowney.

Sudfeld attempted one pass – an incompletion – then Foles returned and completed a 20-yard pass to Ertz that helped keep their game-winning drive alive.

A week later, in the Eagles’ 24-0 win over Washington, Sudfeld played 10 snaps and threw his first NFL touchdown pass on a short toss to Nelson Agholor.

A backup’s challenge

“Life as a backup isn’t easy,’’ Taylor said. “There’s a lot of times where you’re just thrust into a game. It could be at any point in the game.

“As you start a game, guys kind of get the jitters out in the first series and they settle into the speed of the game. Well, as a backup, you come in and you’ve already missed that point of everybody settling in. So you’re trying to catch up and play.’’

Pederson, a former career backup, sees a lot of himself in Sudfeld: a guy who feels he’s good enough to be an NFL starter but understands the importance of the backup role.

“I think he’s got the right demeanor,’’ Pederson said. “He’s perfect for that [backup] role from the standpoint of when he’s in there, he steps up and leads.

“But he’s not looking to push Carson aside and be the guy. He’s there to help Carson and to help him be as successful as possible. At the same time, he’s getting himself ready to play.’’

Said Sudfeld: “One thing with Carson, I just try to be in his ear and see how he likes to run stuff. So that if something happens and I go in, we can kind of stay with the same game plan and I can kind of pick up where he left off.’’