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If you're a fan of the Houston Rockets, your favorite team closed out the first weekend of the NBA postseason with two victories.

Ditto for Philadelphia 76ers and their fully processed crusaders.

The Los Angeles Lakers didn't make the playoffs. Their season is over. And even they picked up a W.

All because the Cleveland Cavaliers didn't.

Sunday's 98-80 Game 1 loss to the Indiana Pacers put LeBron James in an 0-1 first-round series hole for the first time of his career. Many won't be too surprised by the letdown. The Pacers are actually good, and the Cavaliers have looked beyond gone for most of the year. They've been underwhelming enough for James' free-agency exit to be considered in matter-of fact terms.

Except, even at their most broken, the idea that they wouldn't make it out of the first round seemed unfathomable. It existed only in sarcastic form, never serious measure.

Tumbling down to the Eastern Conference's No. 4 seed changed nothing. Nor did the Cavaliers' opponent. Indiana finished 3-1 against them during the regular season. It didn't matter. There were viable excuses.

The Pacers caught the Cavaliers during their annual opening-stretch morass, on Nov. 1, fewer than 10 games into the year. They were a harmless blip, on Dec. 8, amid a stretch in which Cleveland won 18 of 19. And then they pulled the Cavaliers at one of their lowest points, on Jan. 12, when they were barreling toward trade-deadline dissolution and James devolved into an uncharacteristically ineffective crunch-time scorer.

The gap between these two is supposed to be atypical of a usual 4-vs.-5 matchup. The Cavaliers may not have a defensive switch they can flip, and their rotation is peppered with wild cards, but James remains the Eastern Conference's bellwether.

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So, no, the Pacers did not enter this series as a viable threat. Maybe to end James' streak of five consecutive first-round sweeps. But to eliminate him before the semifinals for the first time since his playoff debut in 2006? To be the team that thwarts his eighth straight trip to the NBA Finals?

To be the ultimate wrench in Cleveland's attempt to re-sign James?

That wasn't the Pacers. It couldn't be.

Could it?

Victor Oladipo is adamant Game 1 won't be an anomaly, or even a real surprise. His team wrapped the regular season with 48 victories. Sniffing around 50 wins doesn't happen by accident, and the Pacers spent the final month rattling off single-game takedowns of the Sixers, Boston Celtics, Miami Heat, Los Angeles Clippers (twice) and shorthanded Golden State Warriors (twice.)

"We've been playing like this all year," Oladipo told reporters after Game 1. "We've been playing hard on both ends all year. It just hasn't been magnified. It's the playoffs now, and we've been doing this all year, and now everybody sees it, so it's kind of shocking to everybody, I guess."

Oladipo wasn't merely playing the "Why don't you like my team?!?" and "What about us?!?" cards usually reserved for jilted fans. He has a point, as FiveThirtyEight's Chris Herring noted:

The Pacers' scorching-hot offense cooled off a bit by season's end, but Indiana still finished 12th in points scored per 100 possessions. They are not the sloth-paced plodders from years past. They don't play at lightning-quick speeds either, but they're opportunistic running the floor.

Only eight teams finished a greater share of their offensive possessions on the break. The Pacers were first and fourth, respectively, in efficiency off opponent misses and turnovers, according to Cleaning The Glass.

Things have started to come together for them at the defensive end. They don't allow a ton of looks at the rim or surrender a bunch of wide-open threes. They prioritize getting back in transition without abandoning the offensive glass altogether. Their post-All-Star defensive rating ranked eighth.

Close games do not get to them. The Pacers verged on unreal in the clutch all year. They were first in points allowed per 100 possessions and third in opponent turnover rate. Only the Cavaliers and Rockets notched a better net rating in these situations.

Anyone who expected the Pacers to roll over—or who didn't at least acknowledge they could be more than a sweep or five-game stooge waiting to happen—missed the mark. The Cavaliers were going to feel this series, no matter how long it lasted.

They always seem to feel their postseason meetings with Indiana. Look no further than last year's first-round clash. Their four-game dispatch of the (now-unrecognizable) Pacers was determined by a total of 16 points.

Nothing ever comes easy for these LeBron-era Cavaliers. Something or someone is forever in their way. Sometimes, it's the Warriors. This year, the Rockets have deservedly been added to the list. Most of the time, though, it's themselves.

Players slump. The roster looks old. Nowadays, with Jordan Clarkson, Rodney Hood and Larry Nance Jr. needing to play key roles, it feels inexperienced. The rotation is fluid—far more than it should be for a contender. James goes through periods of intense disengagement, particularly at the defensive end.

Postseason basketball is supposed to be the Cavaliers' exception. For all their faults, they find refuge amid higher stakes. They've always had enough to reach the NBA Finals with relative ease through James' second go-round.

The regular season is where they inflame doubt and hand him the roadmap to leaving Cleveland. The playoffs are where they remind him he has an auto-bid to the Finals.

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To compromise that shaky dynamic is to imperil the Cavaliers' appeal. Many have James leaving irrespective of how the season ends. Others, such as Sports Illustrated's Lee Jenkins, don't see him bolting without a "sure thing" waiting him for elsewhere.

But falling in the first round to the Pacers isn't something for which any prevailing logic has accounted. It wouldn't just invite or incentivize James' exit. It would necessitate it. And with that essentiality comes rationalization, not only from James, but from the outsiders looking in.

Some who wouldn't have initially understood or defended another departure invariably might. After all, how can he, entering his 16th year and age-34 season, stay with a taxed-out team that isn't good enough to deliver on his most basic expectation?

Writing off the Cavaliers now would be senseless. One game doesn't prove anything. They have James. He cannot go anywhere right this moment. And he's unflappable as ever.

"I've always stayed even-keeled with the postseason," he following the Game 1 loss, per ESPN.com's Dave McMenamin. "I mean, I'm down 0-1 in the first round. I was down 3-1 in the Finals. So I'm the last guy to ask about how you're going to feel the next couple days."

More than a few aspects of the Pacers' victory also feel untenable. They shot 60 percent (15-of-25) on contested looks. Oladipo went 7-of-13 on pull-up jumpers, including 4-of-6 from downtown. He's not that much of an off-the-dribble maestro; he barely cleared 38 percent shooting on stop-and-pop looks after the All-Star break.

James tallied a triple-double, because duh. But he won't turn in 7-of-17 shooting performances on the regular—most certainly not when Bojan Bogdanovic is his primary defender. No one guarded James more in Game 1, and the Cavaliers mustered under 0.80 points per possession in those instances.

Other players will have better nights. The Cavaliers shot a combined 7-of-28 (25 percent) on threes where no defender was within four feet of their person and were abnormally reluctant and inaccurate off drives, as Fear The Sword's Mike Zavagno noted:

Kevin Love should never be taking fewer than 10 shots in a playoff game. Ever. Jeff Green should not be on the floor if he cannot capitalize on the Pacers giving him the Andre Roberson treatment with made threes or fruitful drives. George Hill probably won't be battling back issues every game.

Kyle Korver will play more next game if Cleveland is serious about leaning into transcendent offense without fear of defensive repercussions. At least one of Clarkson and Hood should settle down. Head coach Tyronn Lue will adjust. Maybe he busts out the LeBron-at-the-4, Love-at-the-5 offensive cheat code.

Even the most ardent pessimists know the Cavaliers will be better. Indiana limited them to their third-worst offensive rating on the year while having Bogdanovic defend James nearly 60 percent of the time. Props to him, but that's not happening again.

The Pacers are a great story, an underestimated story, even an under-covered story. But the number of things that must continue going right for them to win this series is unsustainably large. They don't have the supporting star power to hang if Oladipo is anything less than extraterrestrial. They are not the team that will turn James' free agency into a non-decision.

They are, however, more than equipped to underscore the fragility in Cleveland.

In a postseason that means everything, the Cavaliers are assured of nothing.

Unless otherwise noted, stats courtesy of NBA.com or Basketball Reference and accurate leading into games on Monday.

Dan Favale covers the NBA for Bleacher Report. Follow him on Twitter (@danfavale) and listen to his Hardwood Knocks podcast, co-hosted by B/R's Andrew Bailey.