PHOENIX — The Boston Celtics had a rare encounter with NBA reality this week.

Until starting their current road trip by falling to the Cleveland Cavaliers and Denver Nuggets in consecutive games, the Celtics had dropped two straight outings only once. That losing streak, if you can call it that, arrived back in November. From that time until the past week, the Celtics were rarely forced to taste their own blood. They were charmed or, perhaps, simply great enough and consistent enough to escape the extended lulls that come for every team. It wasn’t until the first two games on this swing that the Celtics met another skid. They collapsed in the fourth quarter against the Cavaliers before getting swept by the Nuggets in the season series between the two teams.

It wasn’t a long slide relative to the woes most NBA teams go through from time to time. But compared to Boston’s usual smooth sailing, even minor shakiness stood out. Jaylen Brown called it “probably our best little stretch of a challenge in our season.”

“Two losses,” Brown said. “We wanted to respond with a win.”

The Celtics took the test seriously. And they passed it. After soaking up some sunshine during an off day Friday, they overcame a red-hot Kevin Durant and his Phoenix Suns on Saturday night 117-107. Luke Kornet and the bench helped open up a lead in the first half before the starters closed out Phoenix late. Jayson Tatum emerged from an inefficient start to score 13 fourth-quarter points and Al Horford drilled the biggest shot of the night after missing his first six 3-point attempts of the game.

The consequences of another Horford miss could have been severe. With less than two minutes left, the Suns had cut Boston’s double-digit lead to 5 points. Durant had reached a surreal level of shot-making, even by his own lofty standard. Tatum had played the entire second half, putting him above 40 minutes for the night. After four straight empty possessions, the Celtics needed a bucket for a bit of separation. They were in a dangerous spot when Brown initiated an offensive set with a pass to Tatum.

As Brown proceeded to run off a Jrue Holiday screen, Holiday read the defense perfectly and slipped to the paint to receive the ball from Tatum. From there, Holiday forced Horford’s defender to help so he could find Horford all alone in the left corner.

“Just a great play that Joe (Mazzulla) drew up,” Horford said. “I feel like JT made the right pass to Jrue and then Jrue found me in the corner. I took my time. I felt like I was rushing all night my shots, for whatever reason. And that one I just took my time and made sure that I knocked it down.”

Al Horford missed his first six 3s but made his biggest. (Joe Camporeale / USA Today)

The clutch make helped Boston avoid its first three-game losing streak of the season.

“Losing two in a row, on the road, understanding that we needed to get a win,” Horford said. “And we had to do all we had to do just to get this win. And we were able to do it.”

After receiving criticism for a subpar game in Denver, Tatum spent part of his Friday on the links. Though he declined to answer a question about what score he registered on the golf course, he said he won money during the round. The activity allowed him to enjoy the warm weather, a nice treat for the Boston players this time of year. It also allowed him to step away from the mental grind for a few hours, not that he needed too much of a break from that type of stuff.

“I do a pretty good job of moving on,” Tatum said. “I’ve said it before that, regardless of how great I play or I don’t, I’ll never get too down or too high. Whatever people are saying, I respect it. People have a job to report on the things that we do, the things that we say, how we play. So I never take those things personal.”

Tatum hunted fairways. Horford went for a hike and read outside. The Boston players seemed to savor the Phoenix sun. But they were also looking to use the trip to get back on track. Though it almost seemed funny to ask about the emotions of a two-game losing streak, such a common occurrence throughout the NBA, the Celtics hadn’t dealt with much basketball adversity this season. It was fair to question how the players handled the consecutive setbacks.

“I think the most important thing was to handle the losses the way we handle the wins,” Mazzulla said. “So I think the guys showed a great maturity and a great approach to the process when we’re winning, and that’s hard to do. Through the (recent) 11-game win streak I didn’t see much slippage in the effort and details in the things we were doing. So you just have to maintain that through the losses. I think it’s really important to keep that balance, and the guys have done a good job of that.”

The Celtics want to be the same after wins and losses. They want to be the same at home and on the road. They want to be the same every night, every possession, every moment. They won’t always achieve that goal, of course. No team ever will. But they want to be unflappable. They want to be deadly focused on improvement and execution regardless of the situation.

Before beating the Suns, Horford certainly didn’t sound too broken up over the consecutive defeats. His biggest takeaway? He said Boston needs to take care of the ball and get good looks every time down the floor. When the Celtics do that, he said, it covers up the other mistakes they commit.

The Cleveland loss still stung because the Celtics, with a 22-point fourth-quarter lead, appeared to have the game in hand. Instead, they let Dean Wade take on the form of a Hall of Famer and push the Cavaliers into the lead. With one final chance to earn a victory, the Celtics went far too slowly on their final possession, an error of execution they had committed in the past. Two nights later, Boston failed to knock off Denver for the second time in two meetings this season. The reaction to a national spotlight game like that can be fierce, but Horford looked at the setbacks rationally.

“I look at it more from the standpoint of how are we playing,” Horford said. “Is it good basketball? Are we competing? Is it kind of right there? And I feel like these past two games were just two road games against tough teams. Yeah, we had our chances, but we just couldn’t get it done.”

They got it done against Phoenix. They did so even with Durant putting on a relentless shot-making display. They did so even after Tatum struggled for most of the first three quarters and Horford, starting in place of the injured Kristaps Porzingis, couldn’t hit an outside shot for the longest time. Despite playing all of the third quarter, Tatum said he asked Mazzulla to stay on the court for the rest of the game. Even though that would lead to Tatum playing 42 minutes on the night, a lot for a regular-season game, Mazzulla agreed to the request. Tatum said it might have been just the second time all season he asked to play an entire half.

“Just felt like I was getting to a rhythm at some point,” Tatum said. “But I was like, I would make a couple shots then miss three (or) four. The game was starting to get competitive and things like that. I just wanted to stay in. I don’t really say that many times. I just told Joe I wanted to stay in the rest of the game.”

That hints at how badly Tatum wanted a win. Though the Celtics didn’t overreact to the two straight losses, they also didn’t want to make such lapses a habit. They didn’t let themselves fall again.

“Just not letting it snowball effect, right,” Tatum said. “We’re not perfect. We try to be. We really do try. But we make mistakes and things like that. This is a tough league. The other teams are really good, got great players. So it’s all about how you respond. If you want to be a special team, you have to do a really good job of responding. Especially winning on the road is tough, being away from home for 10, 12 days or whatever. So this is a great way to come out here and get a win against a team that’s been playing well lately.”

(Top photo of Boston’s Jayson Tatum shooting over Saben Lee of the Suns during the first half Saturday: Chris Coduto / Getty Images)