The NFL’s 2024 coaching carousel continues to furiously pick up steam. Not even four days ago, three top jobs were open, those vacancies the result of midseason firings. Since then, five more have become available – the New England Patriots' Bill Belichick, Tennessee Titans’ Mike Vrabel and Seattle Seahawks’ Pete Carroll surprisingly ousted in the past 48 hours. Now taking applications, those teams join the Atlanta Falcons, Carolina Panthers, Las Vegas Raiders, Los Angeles Chargers and Washington Commanders.

It’s a fascinating equation, demand obviously on the rise but supply essentially keeping pace when valued commodities like Vrabel and Carroll – hardly uninspiring retreads if they’re quickly scooped up – suddenly shake loose. And now Belichick, arguably the greatest ever at his craft, is floating out there – a massive payday and opportunity to rewrite the record book yet awaiting him ... somewhere.

And while we’re used to something of a coaching arms race this time of year, the league has put the brakes on the process to a degree – needy clubs unable to interview coaches employed by other NFL teams in person until Jan. 22, the day after the completion of the postseason’s divisional round. Of course, those rule don’t apply to everyone.

Regardless, whether they’re explaining their résumés tomorrow or in two weeks, these 21 coaches – listed alphabetically – are likely to be some of the most highly sought … and you never know when the list might expand further, as Thursday showed:

Lou Anarumo

One of the league’s more respected defensive minds – just ask two-time MVP Patrick Mahomes – Anarumo has perhaps been a bit of an unheralded component of the Cincinnati Bengals’ recent rise to prominence. But players love him, play hard for him and make life hell for opposing quarterbacks.

Bill Belichick

What more can you say? Six Super Bowl titles as a head coach and three additional Super Sunday losses with New England. Two more 20th century rings while masterfully pulling levers for the New York Giants defense. Brilliant tactician. And, behind closed doors, not exactly the gruff curmudgeon who presents after his team drops a game (or even wins). Of course, hiring Belichick almost certainly means turning over the keys to your kingdom and accepting the fact that considerations like public relations are not a priority. And any new employer should be wary of his track record as a de facto general manager, which includes prominent misses atop many drafts and during free agency. But you can't argue with 333 wins, now just 15 shy of overtaking Hall of Famer Don Shula's all-time record, or all that ice.

Eric Bieniemy

Always a bridesmaid, never a bride when it comes to HC opportunities – and plenty of conjecture as to why that’s the case. It will be interesting to see how 2023 affects Bieniemy’s bona fides given the struggles he had getting the Commanders offense off the ground – though second-year QB Sam Howell looked pretty dangerous some weeks. Yet it was also apparent the Kansas City Chiefs missed EB following his departure after their Super Bowl 57 triumph – both from a game-planning perspective and his penchant for keeping players honest. He’s expected to get a look as Ron Rivera’s potential replacement in Washington.

Brian Callahan

Anarumo’s offensive counterpart in Cincinnati, Callahan’s ascent has also coincided with the Bengals' and certainly thanks to his work with QB Joe Burrow – though perhaps keeping this team afloat in the second half of 2023 with Jake Browning behind center is a better testament to Callahan’s ability. The Chargers and Panthers have requested interviews.

Dave Canales

After spending more than a decade on Seattle’s staff, he accepted the challenge of taking on the Tampa Bay Buccaneers’ post-Brady offense in 2023 – Canales’ first as an NFL coordinator. Pretty impressive results, Canales balancing the Bucs while coaxing a fine performance out of QB Baker Mayfield. Carolina got two up-and-close looks at Canales, which might explain why they’re considering the 42-year-old as someone to work with QB Bryce Young.

Pete Carroll

He may be 72, but his advancing age has yet to dull his enthusiasm for virtually everything. In one of the NFL’s better second acts, Carroll went 147-98-1 during 14 years in the Pacific Northwest while leading the Seahawks to two Super Bowl and their only Lombardi Trophy. Generally a players’ coach who fosters a competitive meritocracy as the throughline of his culture, Carroll seems to have plenty of juice and desire left – assuming he’s not long for the advisory role he now has in Seattle.

Brian Flores

He earned Super Bowl rings as part of Bill Belichick’s New England Patriots staff, forging a prominent role with BB’s defense. Flores then went 24-25 in three years with the Miami Dolphins before his tenure came to suspect conclusion. He subsequently brought a pending discrimination lawsuit against the NFL and three of its teams, a factor that could compromise his candidacy prior to (and quite possibly after) its resolution. Yet Flores served a solid reminder of his coaching chops in 2023, getting the most of a Minnesota Vikings defense that had its share of personnel challenges.

Leslie Frazier

When you’ve played for the ’85 Bears and coordinated NFL defenses as well as he has for most of the past two decades, you should probably be in the conversation – and the Chargers plan to interview Frazier, who took a year off while dabbling in the media space. He was 18-29-1 during a three-year hitch with the Vikings, including a trip to the playoffs in 2012, despite the team’s rampant quarterback issues following Brett Favre’s retirement following the 2010 campaign.

Aaron Glenn

Three teams (Los Angeles Chargers, Tennessee, Washington) have already requested interviews with the Detroit Lions DC, who was a Pro Bowl cornerback during a 15-year playing career. The Lions have shown steady improvement defensively under the fiery Glenn, who previously spent five seasons on Sean Payton’s staff with the New Orleans Saints.

Jim Harbaugh

Once upon a time, he quarterbacked the pre-Peyton Manning Indianapolis Colts to the brink of the Super Bowl. Years later, he forged Stanford to the brink of a Pac-12 dynasty. Then he rejuvenated the San Francisco 49ers to the brink of their sixth Lombardi Trophy. Finally, after a relatively slow start at his alma mater – the University of Michigan – Harbaugh has won three consecutive Big Ten titles and just guided the Wolverines to their first undisputed national title in three-quarters of a century. Lot to like here, especially for a coach with a talent for optimizing quarterbacks. Also, for well-documented reasons, plenty that could give anyone pause while considering a Harbaugh hire – including the fact he hasn’t declared any intention to leave Ann Arbor.

Ben Johnson

His profile has skyrocketed while elevating the Lions' previously dreary offense the past two seasons. And talk about spreading the wealth: Detroit just became the second team in league history to have four players score double-digit touchdowns. Johnson, who's helped revitalize QB Jared Goff, probably could have gotten an HC job last year had he not withdrawn from the process. Hard to believe he won’t take an opportunity in 2024, though he suddenly appears to have stiffer competition for the choice jobs.

Brian Johnson

An up-and-comer at age 36, he’s helped turn Philadelphia Eagles QB Jalen Hurts into a superstar, though Johnson’s first year as Philly’s offensive coordinator certainly hasn’t ended as well as it started. He also worked with Dak Prescott at Mississippi State and had Kyle Trask and Anthony Richardson, among others, at the University of Florida – and that probably explains why Johnson is another candidate in Carolina as the Panthers try to reroute Young.

Mike Macdonald

Only 36, the bulk of his coaching career has been spent climbing the Baltimore Ravens’ defensive ladder, the past two years as coordinator – this year’s group surrendering the fewest points in the NFL. He did spend 2021 effectively on loan from John Harbaugh to Jim, Macdonald running Michigan’s D in 2021 and turning Wolverines DE Aidan Hutchinson into a superstar. Is Macdonald prepared for the big headset at his age? TBD … but the Panthers and Commanders have already expressed a desire to find out.

Todd Monken

A coaching lifer, Monken, who will be 58 next month, has bounced from the college ranks to the NFL and back. But he’s risen to prominence in recent years, orchestrating the offense of the two-time national champion Georgia Bulldogs before taking the OC role in Baltimore in 2023 and evolving QB Lamar Jackson’s game to the point he’ll probably soon be taking home his second MVP trophy.

Raheem Morris

Hard to believe it’s been 15 years since the Bucs hired a 33-year-old Morris as their head man. Morris went 17-31 in three seasons, though he did have a 10-6 team that just missed the playoffs. But he’s gained seasoning through the years and relishes another opportunity while acnkowledging he might not have been ready for the first one. Two years after running a Rams defense that helped win Super Bowl 56, he’s resurrected that unit despite few recognizable names aside from Aaron Donald’s. And guys who spend any time working with Sean McVay tend to do pretty well once they leave, too.

Antonio Pierce

Very impressive 5-4 stint with the Raiders this season after replacing Josh McDaniels. Pierce, an alpha linebacker for the 2007 Super Bowl champion New York Giants, has spent the last decade honing his coaching skills at every level. They’ve apparently gotten pretty sharp given the endorsements he got from Las Vegas stars like Davante Adams and Maxx Crosby and the interview request he received from Tennessee.

Dan Quinn

For years, he had to live down the fact he led the Falcons to Super Bowl 51, where they infamously imploded against Tom Brady’s Patriots. Since going 46-44 in the ATL, Quinn has rehabilitated his reputation – to the degree that was really necessary – by turning the Dallas Cowboys defense into one of the league’s most opportunistic while fostering the brotherhood environment he so values. Quinn likely could have been on to his next head job had he not opted to remain in Big D, but teams are again lining up for his services. Speculation is already ballooning about a return to Seattle, where he coordinated the legendary “Legion of Boom” before heading to Atlanta.

Bobby Slowik

This season was his first as an offensive coordinator – and what a job he did with the AFC South champion Houston Texans and Offensive Rookie of the Year frontrunner C.J. Stroud. The Ohio State product’s talent has been on full display, Slowik even challenging him with deep drops behind a suspect line but Stroud thriving nonetheless – and with a receiving corps that wasn’t inspiring much confidence prior to the season. At 36, hard to know if Slowik is ready. But he does seem well rounded and well-versed, spending the six seasons prior to 2023 working as an offensive and defensive assistant on Kyle Shanahan’s 49ers staff.

Steve Spagnuolo

After making his bones running the Giants’ Super Bowl-winning defense in 2007, his 10-38 stint with the Rams probably helped drive them out of St. Louis. But Spagnuolo has never been unemployed for long, and none other than Andy Reid has vouched for a second HC opportunity for his current defensive coordinator in Kansas City. The Chiefs’ 2023 defense, which has carried the reigning champs for long stretches, is certainly indicative of Spags’ reputation as a tactician – and his ability to connect with players, sometimes over home-cooked meals, is also quite a cool trait.

Mike Vrabel

He was a great player who won three rings with one of the NFL’s all-time dynasties in New England – a locale to which he might be soon returning? And he’s still young enough (48) and intimidating enough and willing enough to jump into any drill in order to teach proper technique. That aside, he’s a no-frills type who always has his charges ready to go. And his mastery of the rulebook has helped maximize his team’s chances and even enabled Vrabel to outmaneuver Belichick. Teams should be lining up to hire him … and the Titans should get prepared to learn how many warts Vrabel masked for an average-at-best roster.

Steve Wilks

Did he get a fair shot with the Arizona Cardinals despite a 3-13 campaign in 2018? Probably not. Should the Panthers have kept him after he went 6-6 with the interim tag in 2022? Almost certainly. Has he kept moving forward, sustaining the 49ers defense this year after taking over for DeMeco Ryans? Yup. For organizations prioritizing leadership and accountability, prioritizing Wilks makes sense.

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This article originally appeared on USA TODAY: NFL coach candidates: Bill Belichick, Pete Carroll, Mike Vrabel, more