It’s finally time to close the book on an elongated exhibition season. Finally time to wrap up endless discussion about players on the backend of the roster who will sparingly see the field in 2013. Finally time to play meaningful football. Finally time to reveal what these 2013 Miami Dolphins are made of.

Game week is here.

In just six days, the Dolphins will travel to Cleveland to face a team they must beat.

It’s only Week 1. Half of the Dolphins’ 22 starters will be new additions or returning players at a new position from the 22 that took the field one year ago in Houston. The Browns are a potentially much improved team themselves with their own second-year quarterback who is expected to make strides this season. And the NFL is a crazy league, in which anything can happen on any given Sunday.

But save your excuses for someone else.

There are none. Not for these Dolphins. Not for potentially losing this game. Not given the expectations of this season and the schedule that awaits Joe Philbin’s team beginning in Week 2 and culminating in Week 5.

In the second week of the season, the Dolphins travel to Indianapolis to take on one of the league’s best quarterbacks (yes, already) in Andrew Luck. Last season, Luck torched the Dolphins for a rookie-record 433 passing yards. Will Miami’s new-look secondary hold up this time around?

In Week 3, the Dolphins get their first home game, but one of their toughest opponents of the season in the Atlanta Falcons. Matt Ryan and the Falcons are a legitimate Super-Bowl contending team, and anyone who doubts that has qualms about their ability to win big games in the postseason, not as a regular-season team, where they’ve won an average of over 11 games annually since 2008.

In Week 4, the Dolphins will play a team that didn’t qualify for the playoffs a year ago. On the surface, that sounds like a break. But it’s not. Not even close. The New Orleans Saints won as many games as the Dolphins did in 2012, but their lackluster campaign succeeded a tumultuous offseason in which their head coach, Sean Payton, was suspended for the entirety of the year.

Payton is back now. And Drew Brees, who has thrown for over 5,000 yards and 40 touchdowns in back-to-back seasons, is still under center. Not to mention, the Dolphins will travel to the Superdome, where the Saints only lost five times under Payton in his last three seasons as coach.

Some break.

In Week 5 — the Dolphins’ last game before their off week — the reigning Super Bowl champions come to town. Yes, the Ravens lost Ray Lewis. Yes, they lost Ed Reed. Yes, Dannell Ellerbe will be hitting members of the purple and black instead of racking up tackles for said colors.

But they’re still a first-class organization. They still have a championship-caliber quarterback in Joe Flacco, one of the league’s most productive running backs in Ray Rice and plenty of leftover talent on the defensive side of the ball.

A gauntlet awaits. There’s no downplaying it — Weeks 2 through 5 could derail the Dolphins’ playoff hopes before any playoff run commences.

Heading into their bye week at 3-2 would put the Dolphins right on schedule to compete for a playoff spot. Anything better would put them on pace to challenge the Patriots for the AFC East crown.

Sitting at 2-3 would be a disappointment, but depending on how the team hypothetically played, hope, while marred, would endure. Anything worse, and it would be all but official — the Dolphins have been pretenders all along and a new direction will, once again, become imminent.

Losing to the Cleveland Browns is where any doomsday forecast for this franchise would begin to take root. Never mind how crippling that would be for the following weeks, a loss in Cleveland could expose this new-look roster as a fraud from the get-go.

I might be sleeping on the Browns. Maybe quarterback Brandon Weeden is on the verge of a breakout season. But chances are, if the Dolphins lose in Week 1, they’re not the team many say they are.

ESPN The Magazine recently predicted the Dolphins to finish first in the AFC East this season at 10-6. A division-title caliber team doesn’t lose in Cleveland to a club that hasn’t finished with more than five wins in a season since 2007.

Sorry, doesn’t happen. At least it shouldn’t.

Playoff-quality teams do fall to the non-variety on occasion. Oftentimes, in trap games in which the superior squad is looking ahead to a more challenging matchup. But when everything is on the line, a true contender is rarely upset.

And make no mistake about it — everything will be on the line for the Dolphins on Sunday in Cleveland.

It’s not about what they can accomplish by beating the Browns. A win far from validates them as a threat in the AFC.

No, it’s more about what winning would avoid.

The Dolphins have entered many seasons during their decade and change of mediocrity with optimism. Those high expectations have quickly proven impractical for the team in virtually every instance, however.

It all seems more genuine this time around, though. The team just looks the part. The critics certainly haven’t dissipated, but many of the concerns they raise are largely derived from the failures of yesteryear.

The defense is fast, attacking and potentially elite. The playmakers have been upgraded, led by one of the fastest receivers to ever lace up in Mike Wallace. And most importantly, the quarterback — Ryan Tannehill — seems to have it. The oh-so-elusive it that has been evading the franchise since Dan Marino called it a career over thirteen years ago.

But it’s all just perceived at this point. The Dolphins have done nothing to prove they belong among the league’s top teams yet. And a loss to the Cleveland Browns would bring expectations back to reality in a hurry.

Change was aplenty over the offseason. From the marquee free-agent signings to the logo change to the new uniforms, the Dolphins are a rebranded franchise. But a loss on Sunday would likely signify new players in new getups, but the same ol’ Dolphins.

Of course, there would still be 15 games remaining on the slate. Of course, pulling out three wins in the next four weeks would preserve any hope of making this season a special one. But doing so would be an extremely tall order and a hole that may prove too deep to dig out of.

Besides, 2013 is supposed to be a re-defining year for the Dolphins. A season to shake past stigmas that have downtrodden a once proud franchise since the turn of the new millennium.

What would be typical of the Dolphins ensuing on the same course that has resulted in 12 consecutive seasons without a playoff win? Losing to the Browns on Sunday. It’s just what this franchise does.

Substituting “does” for “did” will be the goal in the opener — a first step, albeit small, in validation for the direction this team is headed. In validation for the optimism that finally feels palpable.

The questions have been asked many times since March: Is Ryan Tannehill ready to emerge as a franchise quarterback? Have the Dolphins finally turned the corner? Can they compete for a playoff spot and with the New England Patriots for AFC East supremacy?

Affirmative answers likely won’t be verified in Cleveland with a win, but an unfavorable verdict would certainly become viable in defeat.