The lifeblood of every NFL training camp is always the same: competition.

Offense against defense, aging veterans versus eager rookies, coaches pushing players and teammates stepping over one another as they climb the depth chart.

While quarterback Mac Jones’ wars against Bill Belichick’s defense will be the highlights of summer in Foxborough, Massachusetts, several smaller battles will serve as the building blocks for the Patriots’ upcoming season. Those battles, playing out within several key positions, will determine whether the Pats have enough to ultimately compete when the games count. Will enough quality starters emerge for a playoff campaign or will the team’s weaknesses be laid bare under an unforgiving sun?

Here are the five position battles to watch over Patriots training camp and the preseason.

Kendrick Bourne is battling Tyquan Thornton, and potentially tight end Mike Gesicki, for the No. 3 receiver spot on the Patriots offense. Jeffrey T. Barnes/Associated Press

WIDE RECEIVER

JuJu Smith-Schuster and DeVante Parker can safely be projected as the Patriots top two wideouts. After that? Place your bets.

Kendrick Bourne and Tyquan Thornton will vie for the No. 3 job to start camp, with the potential to supplant Parker. They’ll also contend with tight end Mike Gesicki, who is expected to function like a big slot receiver in Bill O’Brien’s offense.

Last season, the Patriots had high hopes for Thornton, a second-round rookie, before he broke his collarbone in the preseason. Once Thornton returned to the field, he saw more snaps than Bourne, but proved far less productive. Thornton average almost half as many yards per target and finished with fewer total yards, catches and targets.

But, if Thornton – whose 4.2 speed is unmatched across the roster – can make the proverbial Year 2 leap, the complexion of the Patriots offense will change. Opposing cornerbacks must backpedal a few yards deeper pre-snap, safeties will tilt in his direction, and that gravity could draw attention away from other receivers. If not, it’s Bourne’s job.

Provided he beats out Gesicki for snaps on most Sundays, Bourne would introduce a much different dynamic as the No. 3 option. He’s listed at 205 pounds on the team’s website, an indication he intends to be a much better yards-after-catch player this season. A stronger Bourne is a more versatile and dangerous Bourne, but if – and only if – he beats out the speedy Thornton first.

Other names to know include rookies Kayshon Boutte, Demario Douglas and Malik Cunningham, a converted college quarterback.

OFFENSIVE TACKLE

Trent Brown can safely be penciled in to start at left tackle. He’s the most talented offensive lineman on the roster, a 6-foot-8, 380-pounder who at his best acts as an unstoppable force in the run game and immovable object in pass protection. In fact, the only force strong enough to stop Brown seems to be himself.

Assuming Brown maximizes his opportunity in a contract year, the right tackle job will be thrust into the spotlight. Riley Reiff should be the presumed favorite, unless at 34 – after being shown the door by the Bears and Bengals in consecutive seasons – there’s too little left in the tank. If so, former Broncos swing tackle Calvin Anderson is the next man up.

Ideally, two clear-cut starters will emerge from this trio, though if they fail or are sidelined, Conor McDermott should again be called into duty. Signed off the Jets’ practice squad midseason, McDermott exceeded expectations down the stretch last year, but his ceiling appears to be as a swing tackle. After him, it’s fourth-round rookie Sidy Sow, a college guard, and 2022 seventh-rounder Andrew Stueber, who missed last year.

CORNERBACK

Setting aside Jack Jones’ legal situation, Jonathan Jones and first-round rookie Christian Gonzalez project as capable outside cornerbacks, But if there’s an injury? Or Gonzalez hits a rookie wall?

What then?

It’s a question best answered if Jack Jones is available this season and/or Marcus Jones can take over the nickelback position this year. But even if Marcus Jones assumes full-time nickelback duties – a job he’s better suited for than playing outside at 5-foot-8 – the Patriots are thin outside the numbers. Jalen Mills’ move to safety has seen to that, leaving behind only Myles Bryant, professional healthy scratch Shaun Wade and seventh-round rookies Ameer Speed and Isaiah Bolden.

Speed and Bolden can run with most every receiver in the league, but both come with questions about their relative inexperience on defense. Whether they factor into this competition or not, position coach Mike Pellegrino must be at his best to draw the best from this group.

Jabrill Peppers earned praised from Patriots Coach Bill Belichick for his improvement since last year. Peppers is one of the players who will battle to help fill the spot of retired safety Devin McCourty. Greg M. Cooper/Associated Press

SAFETY

Kyle Dugger? Check. Adrian Phillips? Check.

Two of the Patriots’ steadiest defenders will be locks in virtually any defensive package Belichick chooses to deploy, and should be joined by one of Mills or Jabrill Peppers on most snaps. Together, they’ll be charged with filling the free safety snaps Devin McCourty’s left behind in retirement. Last month, Belichick raved about the improvement he’s seen from Peppers, who played free safety for his first two NFL seasons in Cleveland.

“Oh my god, yeah. He’s a much different player now than he was last year at this time or even in training camp. A full year after the injury, a lot of confidence in the communication, the system, his assignments. He’s playing fast, aggressive, helping out his teammates. Last year he was trying to learn things, now he’s helping out his teammates, anticipating, making calls or adjustments that maybe help him or possibly help his teammate be in a better position to defend a certain play or type of play. Yeah, he’s been great.”

And don’t forget about third-round rookie Marte Mapu, one of the darlings of OTAs and minicamp practices.

KICKER

The Patriots drafted Maryland’s Chad Ryland in the fourth round last April, as strong a sign as any they believe he’s their kicker of the future. Ryland boasts a strong leg and experience kicking in cold weather. Ryland was drafted higher than former kicker Stephen Gostkowski, another Patriots fourth-round pick, who lived up to expectations over 14 years in New England as the franchise’s all-time leader in points scored.

So, Ryland’s the guy, right? Well, Nick Folk remains on the roster.

Since joining the Patriots in 2019, Folk has become the most accurate kicker in franchise history. His leg strength has waned, as seen when a 46-yard attempt clanged off the crossbar late last year. He was money within 40 yards, but the lack of power in his right leg also cost the team on kickoffs, where they allowed three returns for touchdowns, most in the NFL.

HONORABLE MENTION: Backup running back, inside linebacker, kick returner, punter