Celtics lose despite going to great lengths

Garnett, playing for the first time since March, converted his first shot, a 16-footer off a Rajon Rondo dish 13 seconds into the game. Garnett hit another jumper, then missed, then sank two free throws after being fouled on an alley-oop dunk attempt. Garnett had 6 points and five rebounds in 13 minutes, departing for good 5:16 into the third quarter.

“I saw his gait and I thought four minutes into the second half he was exhausted,’’ coach Doc Rivers said of Garnett. “I was just watching his gait and as long as he wasn’t limping I was going to let him try and bust through the wall. But then I thought, let’s get him out.’’

After the game, Garnett’s left leg was wrapped in a sleeve, then taped by trainer Ed Lacerte.

“I felt good, I thought I ran well,’’ Garnett said. “Sprint-wise I was not where I want to be. I didn’t play for a whole quarter and, after six months, you’ve got to warm it back up, you know what I mean? For the most part, I felt great out there, I wasn’t hesitant out there, there was no pain. I’m still not where I want to be. Like I said, it’s progress.’’

Asked if he wanted to remain in the game in the second half, Garnett said, “Yeah. That’s not up to me. It’s not going to be something that’s going to change overnight. Like anything else, it’s a continuation, it’s progress. Obviously, playing against the guys we have on this team every day, you have no choice but to get better. I just wanted to see where I was. For the most part, the talking, reaction, it was all there for me. Everything’s coming back. Doc’s on my rear end about attacking and being aggressive, and all that’s just flow. The game is so fast and I was just trying to take it all in and let it all come back to me. It’s all flow. It’s all repetition and getting back into the flow. Like a kid in a candy store, running around with his head cut off; I just have to slow down a little bit.’’

Rasheed Wallace’s first playing time as a Celtic involved giving up a layup to Brian Cook after biting on a fake. But Wallace recovered, hitting his first 3-point attempt, blocking three shots, and being assessed a technical foul. Marquis Daniels airballed his first shot, a 3-pointer, but displayed impressive agility and quickness defensively, handled the ball efficiently, and posted up opposing point guards. Shelden Williams was effective, his stint including a spectacular follow jam after a missed J.R. Giddens free throw.

The game was officiated by replacement referees and the teams took a combined 102 foul shots. Michael Sweetney led the Celtics with 10 points. But the Celtics’ reserves squandered a 6-point lead in the final quarter, the Rockets rallying behind Australian center David Andersen, who scored 7 points in the final 2:47.

In 1990, this was a farming community of 3,292 residents. Last night, 6,300 spectators filled a building that has been sitting atop that farmland for the past six years.

Dodge Arena, a slick, metallic-looking structure, seems out of scale with the surrounding area. The closest major US city to Hidalgo is San Antonio, 232 miles north. But less than half a mile away is Reynosa, with more than 1 million residents, the largest city in Mexico’s Tamaulipas state.

It was a long way to go for the Celtics, who are simply trying to prepare for the start of the regular season. Rivers, for one, would prefer to remain in the Northeast for the team’s preseason. Instead, he found himself nearer to Nuevo Laredo than New England.

“It’s a 4 1/2-hour flight to play one exhibition,’’ Rivers said before the game. “You know where it really hurts you, though, honestly - it kills the next two days. We get back at 5 in the morning, so that day is a blown day of practice. But we make mistakes, we live and we learn.’’

The game was the return part of a deal set up last year, when the teams performed in Manchester, N.H. Rivers jokingly referred to this as a payback.

“They went to Manchester, so they tried to figure out the furthest place they could take us, in the country,’’ Rivers said. “And they cut it very close.’’

Rivers said he discouraged the players from making a border crossing.

“We just basically told them, ‘Don’t,’ ’’ Rivers said. “But I’m not their father. I’m their coach.’’

The Rockets set up training camp in nearby McAllen, and will travel to Orlando, Fla., today. The Celtics will be in Boston, with little time to prepare for tomorrow’s game against New York at TD Garden.

Frank Dell’Apa can be reached at f_dellapa@globe.com.