SANTA CLARA — When the 49ers play St. Louis, and in this case for the second time in three games, coach Jim Harbaugh demands an extra level of concentration to guard against trickery.
San Francisco counts on it from a Jeff Fisher-coached team. The Rams bring it every chance, whether ahead or trailing, and in every phase.
“You've just got to be on high alert at all times. There'll be an onside kick that comes when they're up 14-0,” Harbaugh said. “There's fakes in the punt return game. There's fakes in the punt game, in the kickoff return. Makes us play at a higher awareness, high alert.”
While the 49ers are coming off their bye and have only played once since last seeing the Rams, St. Louis (2-5) is looking for ways to rebound from a 34-7 loss at Kansas City.
“A lot has happened since we played them last,” Fisher said. “I think it's a little different for them because they've only played one game, compared to us where we played two.”
St. Louis has lost offensive lineman Jake Long and wide receiver Brian Quick to season-ending injuries, forcing the Rams to regroup.
The 49ers (4-3), too, were beaten badly their last time out, in a 42-17 defeat at Denver that snapped San Francisco's three-game winning streak.
They're counting on another strong performance against the Rams, despite any wrinkles St. Louis shows this time.
“That's like every team,” wide receiver Michael Crabtree said. “We just got through playing them, so we've got to come back and do the same thing. No matter what tricks they put up we've just got to play.”
Here are some things to watch for Sunday in the Rams' first visit to new Levi's Stadium:
KAEPERNICK'S BIG DAY: After a rough day in Denver two weeks ago, 49ers quarterback Colin Kaepernick needs to return to the form he found in the first meeting with St. Louis.
He threw for 343 yards and three touchdowns, putting the 49ers' comeback into high gear on an 80-yard strike to Brandon Lloyd.
“They have a lot of different things they can unveil,” Kaepernick said. “You just have to be prepared for those.”
TALE OF TWO HALVES: Quarterback Austin Davis and the Rams were on a roll against the 49ers when everything fell apart. As well as these teams know each other, Davis expected himself to respond when San Francisco rallied.
“They made some adjustments,” Davis said. “I didn't really adjust to them as well as I'd have liked. If we have some success they're going to come with something else and we have to counter that. It feels like that was one that got away from us we should have had.”
BOLDIN'S MARK: 49ers wideout Anquan Boldin needs four receptions to become the 17th player in NFL history to reach 900 catches. He would do so in 164 games, the third-fastest in league history behind Marvin Harrison (149) and Andre Johnson (150).
Boldin made seven catches for 94 yards and a touchdown the first time against the Rams.
For St. Louis, tight end Lance Kendricks looks to become the first Rams player with a touchdown catch in four straight games since Torry Holt in 2006.
MARTIN'S DEBUT, ROBINSON'S JOB: Rookie Marcus Martin is set to make his NFL debut as San Francisco's starting center, replacing injured Daniel Kilgore. His teammates and coaches have been impressed how he stayed up to speed in the season's first half while recovering from a dislocated left kneecap sustained in the preseason.
Martin will line up against talented rookie nose tackle Aaron Donald.
“I went against some talented nose guards and some talented front sevens in Stanford and Notre Dame,” Martin said. “But nothing like these guys we're about to face.”
Replacing Long, out with his second straight season-ending knee injury, at left tackle for the Rams will be rookie Greg Robinson. He was the No. 2 overall draft pick last spring.
“Somewhat it is natural. I just feel more comfortable out there, but it's going to be a learning process also,” Robinson said. “It won't take long.”
TRICKY RAMS: While teams prepare for the Rams' trickery, Fisher said St. Louis will still aim for an element of surprise when the timing is right.
Six days after losing to San Francisco, the Rams used two long returns and a punt fake to beat Seattle
“We're going to game plan on special teams the same way we do offensively and defensively,” Fisher said. “If we think we have an opportunity to do something unusual, then that's up to me to make that decision. We're going to try and win ballgames however we can. If it means something unconventional in that phase of the game, then so be it.”