By Michael Hurley, CBS Boston

BOSTON (CBS) — We all expected some form of a quarterback competition in Foxboro this summer. But we did not anticipate this.

While the starting job was Cam Newton’s to lose from the start, it wasn’t beyond the realm of believability for Mac Jones — coming off a tremendous season at Alabama — to make a push for the spot with a solid summer of quarterbacking on the practice field and in preseason games. We all figured we’d be analyzing throws, mistakes, successes, failures, touchdowns, and interceptions.

Instead, we were thrown a curveball. With this.

This, of course, is a mandated five-day absence for Newton, who traveled for a medical appointment on Saturday, underwent some COVID-19 testing but did not undergo the COVID-19 testing required by the NFL, and now must not enter the Patriots’ facility until Thursday, the day of the Patriots’ second joint practice session with the New York Giants.

While the COVID era has provided countless unexpected twists and turns, this one still ranks highly on the surprising scale.

While Newton said earlier this summer that he didn’t care to share his vaccination status, Monday’s news indicates that he is not fully vaccinated. Fully vaccinated players are only tested once every 14 days, and they don’t face travel restrictions. Personnel who are not fully vaccinated must undergo testing through the NFL’s approved lab every day, and they face travel restrictions.

And so, Newton’s decision — while personal — currently figures to have a profound impact on the quarterback position on the New England Patriots.

That the mandated five-day absence for Newton follows his tremendous preseason performance in Philadelphia only adds a deeper layer of fascination to what’s taking place. Newton completed eight of his nine passes for 103 yards and a touchdown, looking comfortable and in control of the offense. Now, less than a year after a lack of preseason and a case of COVID was at least partially blamed for his poor season, Newton is shelved due to COVID-19 protocols that wouldn’t apply to him if he were fully vaccinated.

For Jones, that surprising twist presents an opportunity.

With Jarrett Stidham out and Jake Dolegala gone, all of the QB reps will be going to Jones and Brian Hoyer. And with Hoyer not a real threat to earn the starting job, all eyes will squarely be focused on Jones this week.

That will begin Monday and Tuesday, when the Patriots practice alone. But it will really ramp up on Wednesday, when the Giants come to town for the first of two joint practice sessions. And it will likely extend to Thursday, as Newton may not exactly be at full speed when he returns to work for the first time in a week.

It’s after that — and the preseason finale on Sunday — when things will get really interesting. As of next week, the Patriots will enter regular-season mode, which means the media will only be able to watch team stretching before departing practice. What the Patriots do at the quarterback position in terms of reps and usage will be unknown to everyone who’s not on the roster or the coaching staff. And given the Patriots’ collective ability to keep things quiet, it’s sure to stay that way.

None of that is to suggest that anything will be handed to Jones. But he has been impressive thus far early in his NFL career. He’s completed 26 of his 38 passes (68.4 percent) for 233 yards with no touchdowns or interceptions, good for an 84.6 passer rating. He’s also graded notably highly by Pro Football Focus, which has Jones as the highest-graded QB in the NFL this preseason.

With regard to what it would take for Jones to earn the starting job, Bill Belichick was blunt and succinct when asked about that exact matter on Monday morning.

“Well, I think the fact Cam started last year and he’s here, somebody is going to have to play better than him,” Belichick said on WEEI. “We’re not going to take a job and say, ‘OK, here, this is gift-wrapped for somebody.’ But, training camp is all about competition. There’s an element of who the starter is, but there’s also the competition and in the end the competition is going to decide how things go in any given year.”

Asked about that comment later during his press conference, Belichick’s response was just as simple.

“Again, we all have to reestablish every year our level of performance and our competency. And the guys who have been there, somebody has to show that they’re better than them, or that player has to be unavailable,” Belichick said. “And that’s the way it is at every position. It’s not unique to any position. That’s the way it is across the board. So let’s say you get players that have an opportunity to gain playing time regardless of who else is on the roster or what else is on the roster, by their performance. And that’s the only way I know to do it, so that’s the way I’m going to do it.”

That statement was made before the Patriots announced Newton’s absence. But Belichick noting that opportunities can arrive if another player is “unavailable” rings loudly now.

Given some of the physical concerns that led to Jones being the fifth quarterback taken in the draft, he is perhaps ahead of schedule. Those concerns may prove to be enough to make this entire conversation moot.

Yet Newton’s unscheduled absence nevertheless presents an interesting wrinkle in what has been a fascinating story line in Foxboro this summer. It’s possible that it ends up being a footnote in the eventual call for Newton to remain the starting quarterback through the start of the season. But it’s still an undeniable chance for the rookie to change some minds, in a league where careers can be made by young players seizing opportunities that arose unexpectedly.

For Jones, that opportunity might have arisen earlier than he planned or hoped. But, in the form of the enforcement of a COVID testing protocol for a veteran player, it’s unquestionably arrived.

Bill Belichick, Mac Jones (Photo by Mitchell Leff/Getty Images)

You can email Michael Hurley or find him on Twitter @michaelFhurley.