HOUSTON — The Celtics were in the game, right there with the Rockets, the score all tied up. They hadn’t missed one shot, made one mistake, and hadn’t given up a single basket, either.
And then the referee tossed the ball up.
Four minutes later, the Rockets led, 18-1.
By that point, the Celtics had missed all nine of their field goal attempts, had turned the ball over twice, had committed four fouls, and had four of their shots blocked.
Any small achievement from then on — such as a made basket, the first of which came with 6:46 in the first quarter — seemed like a momentous achievement for a rebuilding Celtics squad in way over its head against a playoff contender.
And small victories were all the Celtics could take out of Tuesday’s game against the Rockets, because they sure didn’t leave the Toyota Center with a win after being blasted, 109-85.
“I don’t know what the [expletive] that was, to be honest,” swingman Gerald Wallace said.
Just a bad loss, the Celtics’ fourth in a row, dropping them to 4-8?
“I don’t think it’s all that,” Celtics coach Brad Stevens said. “I think there’s more to it. I want to make sure we don’t play like that again, so I never look at it as, ‘Hey, it was just one of those things,’ because there is something behind when you don’t play the way you’re supposed to.”
It was the Celtics’ most lopsided loss of the season, a pure stinker that they trailed by as much as 35.
“It’s going to take a lot to get over this game,” said guard Courtney Lee, who led the Celtics with 17 points off the bench. “Everybody’s going to be thinking about it.”
The most points the Celtics have ever allowed is 160 against Detroit on March 9, 1979. And the Rockets (8-4) were on pace to match that figure after the first quarter, when they led 40-18 and had shot a blistering 80 percent, making 16 of 20 shots.
Can an entire game be classified as garbage time? It sure felt that way, and also like a varsity squad filled with seniors was playing against eighth graders.
“I feel like everybody individually can control their effort and I don’t feel like we gave our full effort tonight,” Avery Bradley said, a familiar line multiple Celtics have used so far this season.
The Rockets led, 68-44, at halftime and had huge advantages in points in the paint (36-12) and fast-break points (19-1).
“No, I don’t feel helpless, because I knew I was going to lose games before,” Stevens said. “A lot of the things that are going through my head at that time are big-picture things, long-term things, later tonight things, tomorrow things, how to best use this to move forward in a positive manner, which is not easy.”
Jeff Green, tabbed as the Celtics’ go-to player before the season, was again a nonfactor.
He didn’t even make a shot until the third quarter, which broke a streak of seven consecutive quarters in which Green had yet to even make one field goal. He finished with 4 points.
The Rockets had six players score in double figures, including all five starters.
Terrence Jones scored 24 to lead the home team. Dwight Howard had 10 points and 11 rebounds in 28 minutes. James Harden added 15 points. The Rockets shot 57 percent.
“I just don’t feel like we gave a lot of effort tonight on the defensive end,” Bradley said. “I know the coaches keep harping it and the players as well. We just have to play better on defense. “
Wallace agreed, and spoke to the team about it after the game.
“As a team, we have a bad habit of allowing our offense to affect how we play defense,” he said. “When we’re not making shots, if things aren’t going good for us offensively, we struggle bad defensively.”
Stevens said that aspect — letting a poor offense affect their defense — was the most disheartening part of an overall terrible performance.
“Until we establish a defensive mind-set, then you’re not going to be able to stay in games, like tonight, where you’re struggling to score,” he said.
Stevens added, “The biggest key right now is trying to fix it, [whether it’s] personnel, which it very well could be, or whether [it’s] scheme, which it very well could be. So we’ll look at it all.”
Maybe the Celtics’ losing ways are just a product of their division, the Atlantic, where, as of Tuesday, all five teams — Philadelphia, Toronto, Boston, New York, and Brooklyn — have collectively lost their last 14 games.
Even with the loss, the Celtics are one game back of taking the lead in the division, but its unlikely they’ll get that win this week, as they play the Spurs in San Antonio on Wednesday and then Indiana on Friday at TD Garden.
“We’re . . . 12 games into the season,” Wallace said. “We’ve got about  more of these.
“If you want to look up and you’re down 30, or you’re giving up 40 points in the first quarter, for the next  games, that’s going to be a long season.”
It might feel long up until the NBA Draft Lottery, May 20, 2014.