It was just after midnight back in San Antonio when Tim Duncan emerged fully clothed from a back room at Oracle Arena, eased himself into a chair in front of his locker and emitted the worn-out groan of grandpa melting into his favorite recliner for a “Matlock” marathon.

Just finished with a six-game Western Conference semifinal series against Golden State that had taxed him like seven, the Spurs' weary 37-year-old big man already was steeling himself for what lies ahead.

Next up, the Memphis Grizzlies — all grit and grind, broad shoulders and wider backsides, and headed to the AT&T Center to open the conference finals Sunday afternoon.

“If you thought this was physical,” Duncan said, “it's going to turn up about 10 notches.”

It was a warning mostly meant for himself.

Back in the West finals for the second consecutive season, and the third time since the Spurs' last NBA championship in 2007, Duncan faces the prospect of going seven games against the black-and-blue Grizzlies, and their frontcourt built like a defensive line.

For the Spurs' big men, six games of hedging pick and rolls to help on Golden State's fleet-footed guards was tiring in the way chasing cats is tiring.

Squaring off with Zach Randolph and Marc Gasol will be tiring the way being perpetually run over by a Mack truck is tiring.

Randolph is 6-foot-9 and 253 pounds and attacks the glass as if it had insulted his mother. Gasol is 7-1 and 265 pounds, with a sandpaper toughness that belies the more finesse aspects of his game.

Together, they have dragged the fifth-seeded Grizzlies into the first conference final in club history, by a brand of basketball permanently caked in mud.

“It's not going to be pretty, I'm sorry,” Duncan said, as network television executives pour themselves another round.

“It's going to be two teams trying to impose their wills on each other.”

Randolph is averaging 19.9 points and 9.3 rebounds in the postseason. Gasol, the reigning Defensive Player of the Year, is averaging 18.3 points, 7.9 rebounds and 2.2 blocks.

No team enjoys wallowing in the dirt quite like Memphis. The Spurs learned as much two years ago.

Behind Randolph's postseason coming-out party, the Grizzlies became the second No. 8 seed in the best-of-7 era to knock off a No. 1. The Spurs have viewed the Grizzlies as a threat ever since.