By Scott Cacciola

New York Times News Service

Trail Blazers 3, Thunder 1

Game 1: Blazers 104, Thunder 99

Game 2: Blazers 114, Thunder 94

Game 3: Thunder 120, Blazers 108

Game 4: Blazers 111, Thunder 98

Tuesday at Portland 7:30 p.m.

x-Thursday at OKC TBA

x-April 27 at Portland TBA

All times PDT; x-if necessary

OKLAHOMA CITY — In their first meeting at the start of training camp, it was among the first topics of conversation.

The Portland Trail Blazers were not going to ignore what had gone wrong for them in the playoffs last year, probably because ignoring it would have been impossible even if they tried. Many of them had spent the summer dwelling on it.

“We were just really motivated,” second-year center Zach Collins said. “Especially after last year.”

Last year, the Trail Blazers entered the NBA playoffs as the third seed in the Western Conference — and were promptly swept in the first round by the New Orleans Pelicans. After his team’s quick exit, guard C.J. ­McCollum fled to Europe, where his older brother Errick was playing pro basketball for Turkish club Anadolu Efes. But the trip provided only temporary relief.

McCollum recalled an offseason of near-constant criticism, or at least that was the way it felt to him. Every time he turned on the TV, he said, he heard the same questions, the same noise: Should the Trail Blazers trade him? Could this team ever actually win together?

“It was really embarrassing,” McCollum said.

But rather than fold under the weight of failed expectations, the Blazers were determined to seize a fresh start.

“I approached it the same way I always do: as a challenge,” McCollum said late Sunday night, after helping the Blazers defeat the Oklahoma City Thunder, 111-98.

The win gave the Blazers a three-games-to-one lead in their first-round playoff series. “I take this game very seriously, and I’m thankful that I was able to go through those struggles, because it made me a better person.”

Those struggles also made the Blazers a better team, with greater balance and more toughness. They have another opportunity in front of them now, with a chance to close out the best-of-seven series at home Tuesday night against an opponent that is reeling.

On Sunday, Russell Westbrook had another one of his gluttonous shooting nights for the Thunder. He is a basketball magician, a unique talent in a league full of dynamic players. But his mentality — press ahead, no matter what, especially in the playoffs — can be costly, and he scored only 14 points while shooting 5 of 21 from the field. He missed all seven of his attempts in the second half as Portland packed the paint and turned him into a midrange shooter.

“Just playing tendencies,” the Blazers’ Damian Lillard said.

Lillard, the point guard, tends to take a different approach. If he is struggling, he still tries to create — but for others, with his passes. On Sunday, for example, he missed his first six field-goal attempts, but they were spread out over much of the first half. He never looked rattled or impatient. Instead, he deferred to teammates like McCollum and Al-Farouq Aminu, who combined for 23 points as the Blazers took a 50-46 lead into halftime.

“I loved it,” Lillard said, adding: “I didn’t feel the need to try to get overly aggressive in that first half once I saw how that game was going.”

But at the start of the second half, Lillard decided, in his words, to “hit the gas.” He scored 15 of his 24 points in the third quarter as the Blazers extended their lead to as many as 19, which proved too much for the Thunder to overcome.

Portland has experienced its share of adversity in recent weeks. Jusuf Nurkic, the team’s starting center, broke his left leg last month and was lost for the season. And McCollum missed 11 of the team’s final 13 regular-season games after straining a muscle in his left knee.

But McCollum has been terrific against the Thunder, averaging 26.3 points in the first four games of the series while shooting 51.6% from 3-point range. And Enes Kanter, who signed with Portland after he was released by the New York Knicks in February, has been solid in Nurkic’s absence, averaging 13.3 points and 9.5 rebounds while starting at center against Oklahoma City.

“We just trusted each other more,” Lillard said of all the obstacles. “It just made us better in the long run. Instead of us saying, ‘OK, we’ve got some injuries: Dame, you’ve got to average 35 and do all this extra stuff.’ Instead of that, the mentality was: Let’s keep the ball moving. Let’s make the right plays. Let’s be better defensively. Let’s just be a better unit instead of turning to me. We made it a group thing.”

McCollum, who finished with a team-high 27 points in Sunday’s win, said he knew that his older brother was keeping odd hours in Russia, where he is playing this season, so he could keep tabs on the Blazers. But he should not expect another visit anytime soon.

“I told him this year,” ­McCollum said, “‘I ain’t going to be able to make it.’”