McDonald makes his mark with breakthrough game.

Byline: Cam Inman

SANTA CLARA, Calif. _ It didn't take long for Ray McDonald to shake up things up as the 49ers' new starter at left defensive end.

He was a force on Sunday's opening series, capped by a third-down sack of Seattle Seahawks quarterback Tarvaris Jackson. That fell in line with coach Jim Harbaugh's scouting report on McDonald.

"We all felt here's a guy that is just about ready to explode onto the scene," Harbaugh said Tuesday. "It's like there've been some earthquake tremors reported on the Richter scale. Here's a guy where 'The Big One' could be coming.

"That's why he was such a high priority for us to re-sign. He had a marvelous game."

McDonald, a third-round draft pick in 2007, landed …