SAN ANTONIO — The San Antonio Spurs opened the Western Conference finals Sunday resembling the past champions who’ve been there so many times before.
The Memphis Grizzlies looked like the first-timers still trying to adapt to their first conference finals appearance.
Tony Parker had 20 points and nine assists, Kawhi Leonard scored 18 points, and the Spurs struck first by beating Memphis, 105-83.
San Antonio raced out to a 17-point lead in the first quarter, then came up with a response when Memphis rallied to get within 6 in the second half. Both teams pulled their starters with more than five minutes left and the Spurs up by 21.
‘‘I can promise you this: Nobody’s happy in our locker room, because we were up 2-0 [in the West finals] last year and lost,’’ Parker said. ‘‘It’s just one game. It means nothing. We still have a long way to go.’’
The Spurs avoided a repeat of their Game 1 loss when the teams met two years ago in the first round. The Grizzlies went on to knock San Antonio out of the playoffs as the top seed that time around.
Memphis has lost its opener in each round in this year’s playoffs, recovering from a 0-2 hole in the first round against the Los Angeles Clippers and a 0-1 deficit against Oklahoma City in the West semifinals.
‘‘We just didn’t play well. It’s not anything specific,’’ Grizzlies coach Lionel Hollins said. ‘‘It’s just that we were running too fast, we missed some layups, we were taking bad shots, and our defense was really awful. And the Spurs played well.’’
The NBA’s stingiest defense wasn’t up to its usual standards, allowing the Spurs to hit 53 percent of their shots and a franchise postseason-record 14 3-pointers while All-Star power forward Zach Randolph struggled. Randolph had just 2 points, getting his only basket with 9:26 left in the game.
He had a playoff-best 28 points and 14 rebounds in his last game, as Memphis eliminated defending West champ Oklahoma City in Game 5 on Wednesday night.
‘‘Obviously, he’s their best scorer. He’s a beast inside,’’ Parker said. ‘‘We know he’s not going to play like that every game. It sometimes happens.’’
Quincy Pondexter led Memphis with 17 points, Marc Gasol scored 15, and Mike Conley had 14 points and eight assists.