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The Houston Rockets continue to roll after their 115-104 victory over the Boston Celtics at TD Garden on Sunday.

Since losing to the Los Angeles Lakers on Feb. 21, the Rockets have responded by winning their last five games. The defending Southwest Division champions are a season-high 13 games over .500 at 38-25 following their victory over the Celtics.

James Harden followed up his 58-point effort against the Miami Heat with 42 points on 14-of-31 shooting before fouling out late in the fourth quarter. Eric Gordon had his most prolific scoring game since Nov. 26 with 32 points on 8-of-12 three-point shooting. Chris Paul added 15 points and 12 assists.

Kyrie Irving led Boston's offense with 24 points and nine rebounds.

It's Time to Stop Treating the Celtics Like a Contender

The best and worst thing that can happen to a team in any sport is expectations. It's a burden because unless you play perfect every single night, there will be criticism about even the most minute detail.

Expectations can also serve as a crutch, constantly propping up a disappointing team because everyone remembers why they fell in love in the first place.

The Celtics raised their expectations sky-high last May when they made it to Game 7 of the Eastern Conference Finals without Gordon Hayward virtually all season and without Kyrie Irving for the postseason.

With Hayward and Irving returning this season, Boston's over/under win total was set at 57.5, second in the NBA to the Golden State Warriors (62.5).

At what point does it become time to accept that a team just isn't going to become what everyone assumed it would be?

In the case of the 2018-19 Celtics, the answer came Sunday. Things have been so bad for them since the All-Star break (1-5) that Friday's win over the Washington Wizards felt like a cause for celebration:

Much of the focus during Boston's post-All-Star malaise has been on the offense, and it's been difficult to watch:

But the Celtics' usually stout defense has looked lost over this six-game stretch. They've allowed 108.3 points per game and don't look aggressive when opponents drive to the basket.

Late in the second quarter, Jayson Tatum allowed an easy finish for Harden after the reigning MVP turned Marcus Smart around and blew right past Al Horford:

Of course, Harden also made life difficult for the Celtics by draining his own ridiculous shots when they were playing good defense:

The combination of no ball movement on offense and flat-footed defense left the Celtics in a position where the Rockets were essentially doing whatever they wanted.

Head coach Brad Stevens rightly earned plaudits for being able to maximize the talent on his roster, whether it was with the Celtics or during his time at Butler. This was the first season when he appeared to have one of the most talented rosters in the NBA.

For whatever reason, though, these Celtics have never played up to their full potential. Their identity has seemingly been in a constant state of flux with Tatum, Hayward and Jaylen Brown struggling to find chemistry with each other.

There's also the elephant in the room that is Irving's future. The All-Star guard can opt out of his deal this summer and has been noncommittal about staying in Boston:

Boston's recent skid has led to Irving seemingly unable to hide his disdain:

All of these points add up to a team that has done nothing to be considered a true championship contender in the Eastern Conference.

The Celtics are currently the No. 5 seed, with every team in the conference behind them at least one game under .500, for a reason.

So much time has been spent this season wondering when, or if, the Celtics will be able to flip a switch when the playoffs arrive.

"Like I said, I don't get frustrated about this stuff anymore," Irving told reporters after a Feb. 23 loss to the Chicago Bulls. "It's just part of the regular season. In the playoffs, when we can plan for a team, prepare for a team, I still don't see anybody beating us in seven games."

You can see where Irving is coming from; even in Sunday's loss, there were signs of the good Celtics emerging. They got within eight with under two minutes remaining in the fourth quarter after trailing by as many as 28 points.

But Stevens acknowledged after Sunday's loss the Celtics waited too long to get back in the game.

"The game was lost in the first 30 minutes," Stevens said, via Adam Himmelsbach of the Boston Globe.

It's good that Irving maintains a high level of confidence, because the Celtics aren't showing anything in their on-court performance to suggest they will challenge the Milwaukee Bucks or Toronto Raptors in a playoff series.

What's Next?

The Rockets will wrap up their brief two-game Atlantic Division road trip Tuesday against the Toronto Raptors. The Celtics will begin a four-game Western Conference road trip Tuesday against the Golden State Warriors.