LAS VEGAS -- Star forward Zion Williamson claimed accountability for the New Orleans Pelicans' failure to compete in the most meaningful game of his career.

The Los Angeles Lakers rolled to a 133-89 rout of the Pelicans in Thursday's semifinals of the NBA's in-season tournament at T-Mobile Arena. It ranks as the third-most lopsided regular-season loss in the New Orleans franchise's history.

Williamson agreed with Pelicans coach Willie Green's assessment that there was "just a lack of competitive spirit from our group" and blamed his timid play for setting the tone. Williamson finished with 13 points, 2 rebounds, 3 assists and 3 turnovers in 26 minutes, during which the Pelicans were outscored by 33 points.

"I got to be better," Williamson said. "I got to be more aggressive, finding my shot. I got to do more things to get my team going. I think I was too laid-back tonight and I just can't do that. And defensively I got to be better."

Lakers star LeBron James was a dominant force with 30 points, 5 rebounds and 8 assists in only 23 minutes. James sat out the entire fourth quarter after the Lakers blew the game open by outscoring the Pelicans 43-17 in the third.

"Tonight was a total letdown," Pelicans coach Willie Green said. "We were all disappointed in our competitive spirit against the Lakers, and you got to give them credit. They came out and they dominated."

Green cited the Lakers' significant experience advantage as a factor. James and center Anthony Davis (16 points, 15 rebounds, 5 assists) were the centerpieces of the Lakers' run to the 2019-20 championship, the fourth title of James' career.

Williamson, in contrast, has yet to play in an NBA postseason game. He was sidelined for play-in games the past two seasons and the Pelicans' 2022 playoff appearance because of injuries.

"They know what it takes to be on the big stage and have big moments," Green said. "For some of our guys, this is their first time since college being in elimination games. So we'll take the experience, we'll watch film on it, we'll grow and we'll learn. For Z in particular, it's a moment that we can learn from. The level went up tonight, and like I said, we didn't match their intensity."

Williamson wasn't as impactful as usual in the Pelicans' in-season tournament quarterfinals win over the Sacramento Kings, either. He was held to 10 points on 5-of-8 shooting in that game. He was 6-of-8 from the floor in Thursday's loss.

"I have a problem where I literally just try to hunt the best shot possible every time, but my teammates, they expect more from me," Williamson said. "I expect more from myself. I got to just trust my game. I just got to be more aggressive. I think if I'm more aggressive that energy will definitely carry over."