Among the opening scenes of Avengers: Endgame, Tony Stark sits on what amounts to a sinking vessel and stares in the void not knowing exactly what's to come. The same feeling can be attributed to multiple high-profile coaches around the NFL. They don't know exactly if their situation will drastically improve in the near future or result in failure.

Each will certainly try his best to rectify what went wrong this past season and get the job done. But they do so with full knowledge that another year of disappointment will almost certainly cost them their jobs.

In multiple instances, smaller moves have already been made to act as a buffer between needed change and a complete overhaul. The fact of the matter is that 18 teams didn't make the postseason. Among those franchises, five fired their head coaches, while six others made significant changes to their current staffs.

"We're going to evaluate on how we can get better," Washington Commanders head coach Ron Rivera told reporters during his end-of-season press conference. "There is a fine line."

Anytime those type of moves are necessary, an uneasiness begins to invade an organization, because everyone knows the next step brings finality for those currently steering the ship. As such, the fine line, as Rivera described, is removing what's perceived to be the problem without laying the entire blame on those who are making the decisions.

We're now in the endgame for five coaches hoping their fates don't ultimately end in their professional demise.

Brandon Staley, Los Angeles Chargers

Some may say that Brandon Staley was lucky to survive this year's chopping block based on how the the 2022 campaign ended.

First, he played his starters in a Week 18 contest that had no playoff seeding implications. In doing so, standout wide receiver Mike Williams suffered a fractured back during the 31-28 loss to the Denver Broncos that prevented him from participating in the team's postseason contest.

Then the Chargers quickly bowed out of the playoffs by squandering a 27-0 second-quarter lead to the Jacksonville Jaguars, who ultimately won 31-30.

All of this came a year after Staley inexplicably called a timeout in overtime against the Las Vegas Raiders that gave their rival enough time to win the contest and capture a postseason berth. Staley could have easily played for a tie, which Las Vegas seemed to be doing at the time, and both squads would have gotten into the dance.

Clearly, Staley's decision-making in critical moments has been questionable, at best. But the organization has long been known for finding ways to lose in unbelievable fashion, hence the term "Chargering."

What can't be overlooked is the team's 19-15 regular-season record since Staley became the head coach. During the previous two seasons, Los Angeles won 12 total contests. This uptick bodes well, though Staley has felt the squeeze coming out of the team's latest letdown.

The second-year head coach fired his offensive coordinator, Joe Lombardi, and quarterbacks coach, Shane Day, after the season. If the Chargers don't maximize what they have in quarterback Justin Herbert, Staley knows what happens next.

"You understand the way it is and that there's always going to be speculation when other people may not be thinking that you are having the success that they think you should have," Staley said of being on the hot seat.

Kevin Stefanski, Cleveland Browns

Being named the NFL Coach of the Year isn't necessarily a boon for an individual's career. Recent winners have a spotty track record.

Kevin Stefanski deservedly won the award following the 2020 campaign after leading the Cleveland Browns to their first playoff appearance in 18 years and first postseason victory in 26 years. However, the team experienced a downward trajectory over the following two seasons with 8-9 and 7-10 records in '21 and '22, respectively.

The next step is figuring out whether Stefanski fits into the category of a Mike Vrabel, John Harbaugh or Sean McVay, who proved they are long-term answers at their respective stops after winning the same award. Or does Stefanski fall in line with Ron Rivera, Jason Garrett and Matt Nagy after they didn't build upon that success and got served their walking papers years later?

Stefanski is now entering that window in his fourth year with the franchise. The former offensive coordinator and assistant coach shows an aptitude for building a strong offense, particularly when he scripts his initial plays. However, in-game adjustments and situational awareness tend to be lacking.

Another growing concern is how much control Stefanski has over his locker room. Multiple Browns came out publicly this year to criticize the performance of others and how they were handled. Jadeveon Clowney's outburst prior to Week 18 served as the thunderhead for this dark cloud.

"There's gotta be better communication across the board and there's gotta be a steady dose of leadership from the top down and we've gotta squash all this before it comes to a head like this," All-Pro defensive end Myles Garrett told reporters.

Most, if not all, of the animosity seemed to come from the defensive side of the ball, where the Browns continually suffered from on-field miscommunication and schematic breakdowns. As a result, Stefanski fired Joe Woods and hired veteran coach Jim Schwartz.

A better defensive performance coupled with a full year of working with Deshaun Watson could save Stefanski's spot. If the Browns suffer through another rocky campaign, change is almost certainly coming.

Ron Rivera, Washington Commanders

Ron Rivera is a slightly above-average head coach.

The Washington Commanders boss holds a career 98-90-2 record between two different franchises. In fact, in eight of his 12 seasons, he's posted a losing record. His overall record is buoyed by the year the Carolina Panthers went 15-1 and made an appearance in Super Bowl 50, which they lost.

Rivera's time in Washington has been marred by mediocrity. The team has won seven, seven and eight games in his tenure.

With the Commanders' playoff hopes on the line, Rivera made the inexplicable choice to start Carson Wentz after only one appearance in 10 weeks during garbage time in a Week 16 loss to the San Francisco 49ers. Unsurprisingly, the quarterback played terribly with three interceptions in the 24-10 loss to the Cleveland Browns.

To make matters worse, Rivera apparently didn't know his team could be eliminated from the postseason with the loss—which it was.

The status of Washington's organization, as a whole, hasn't been easy to navigate. Owner Daniel Snyder has been under federal investigation and he's now considering a sale. Overall, Rivera has been a steadying presence for the entire franchise.

But Washington needs on-field results. The offense is in disrepair without an established quarterback. Rivera dismissed offensive coordinator Scott Turner after the season. As of now, the organization plans to go into the season with 2022 fifth-round draft pick Sam Howell, even after just one start as a rookie.

Unless something is figured out at quarterback, Rivera probably can't survive another season with seven or eight victories.

Todd Bowles, Tampa Bay Buccaneers

The Tampa Bay Buccaneers will look drastically different at the start of the 2023 offseason than they did a year prior.

Bruce Arians resigned as head coach in late March 2022, clearing the way for Todd Bowles to take over. Bowles will still be in place, but the Bucs announced Thursday that they fired offensive coordinator Byron Leftwich and five other assistants. Quarterback Tom Brady is heading into free agency, as are Lavonte David, Julio Jones, Akiem Hicks, William Gholston, Rakeem Nunez-Roches, Sean Murphy-Bunting, Aaron Stinnie, Keanu Neal, Carl Nassib, Logan Ryan, Jamel Dean, Anthony Nelson and Scotty Miller.

"Never rebuild. You always reload," Bowles told reporters after Tampa Bay's 31-14 loss to the Dallas Cowboys in the Wild Card Round. "You feel like you have a chance to win every year. You've just got to tweak some things from a schematic standpoint all the way around—offense, defense and special teams. Obviously, no one ever comes back with every player on the team, so we'll have some new faces in here. That's just part of the game."

It won't be easy for the Buccaneers to reload, though. They're already $55.5 million in the red to enter the offseason, per Spotrac, and that isn't counting any of the players who are heading into free agency.

Bowles landed the Bucs' head coaching gig because Arians unexpectedly chose to step down. Tampa Bay won the the NFC South only because it's arguably the NFL's worst division, and it still couldn't manage a winning record. The offense was in disarray. Injuries marred the campaign. And multiple key contributors appear to be heading out the door.

Tampa Bay maximized its short Super Bowl window, but it's now time to rebuild. Bowles will have to do an exceptional job with what's left over to retain his position beyond the 2023 season.

OC Matt Canada, Pittsburgh Steelers

Maybe it's unfair to include Pittsburgh Steelers offensive coordinator Matt Canada alongside four NFL head coaches. However, Canada's standing with one of the league's most stable and high-profile organizations shouldn't be entirely overlooked just because head coach Mike Tomlin isn't on the hot seat.

Canada came under significant fire over the past two seasons after the Steelers finished among the league's bottom 10 in total offense both times. Granted, Ben Roethlisberger was incapable of pushing the ball downfield in 2021, and Canada had to groom the future Hall of Famer's first-round replacement in Kenny Pickett. Both limited what the system could do.

The Steelers showed signs of life late in 2022, with Pickett leading comeback victories against the Las Vegas Raiders and the Baltimore Ravens. However, the Steelers offense faltered for long stretches in both of those wins.

"I thought he got better just like our team got better," Tomlin said last week about Canada's performance. "... We have some work to do, but largely I thought he got better in the ways that we got better, so it was encouraging."

The Steelers currently plan to bring Canada back next season, according to the Pittsburgh Post-Gazette's Gerry Dulac. He has one year remaining on his contract, per Dulac.

Continuity can be a positive for a young quarterback as he gets comfortable in a scheme. However, the Steelers could end up in the same place next offseason that they are right now—weighing whether to replace Canada because he didn't show enough improvement.