SANTA CLARA — The San Francisco 49ers hadn’t had time to bask in the glow of their fourth straight win to open the season when the attention turned to next week.

Sure, a 4-0 start with at least 30 points in every game was reason for encouragement for the 49ers, who beat Arizona 35-16 on Sunday.

But they know that won’t mean much if they can’t win next Sunday night in a showdown against the 3-1 Dallas Cowboys.

“That’s OK,” star left tackle Trent Williams said of the team’s fifth 4-0 start in franchise history. “As soon we finish one game, we’ve got to look forward to the next one. Yeah, you celebrate wins. … But at the end of the day you got the Dallas Cowboys rolling in, and resting on a four-game winning streak doesn’t really seem like the thing to do right now.”

49ers Yet to Be Tested This Season

The Niners are hitting on all cylinders ahead of their matchup against one of the NFC’s leading contenders and the team they knocked out of the playoffs the past two seasons.

Behind an efficient performance from quarterback Brock Purdy, a four-touchdown game from Christian McCaffrey, and another solid defensive effort, the 49ers won their third game by at least 18 points.

Their closest contest was a 30-23 win in Week 2 against the Rams that included a field goal by Los Angeles on the final play to make it a one-score game.

But they are counting on a tougher test this week against Dallas and are excited for the big stage.

“I’m a fan of football, first growing up and everything, and still am now,” coach Kyle Shanahan said. “So any time there’s big matchups and stuff, especially for the night games. That’s what’s great for our league. There’s nothing more fun than being a part of it as a player or coach. These are kind of the games you look for and enjoy.”

Cowboys Must Overcome Mental Hurdle

The mental hurdle of facing the unbeaten 49ers (4-0) is substantial for the Cowboys, who have lost to San Francisco in the playoffs each of the past two seasons.

Cowboys QB Dak Prescott had a long pause before his answer to what ended up being the final question he took after Dallas manhandled New England, 38-3, on Sunday. He said it couldn’t be more obvious what the locker room was like after the 19-12 divisional round loss at the 49ers last season.

“We’re so far past that, to be honest,” Prescott said.

Defensive end DeMarcus Lawrence was asked when the attention will turn to the 49ers.

“Is that who we play next week?” Lawrence asked, somewhat rhetorically while getting “yes” for an answer. “All right. I’ll turn to San Francisco on Tuesday.”

WHAT’S WORKING

Getting the ball to McCaffrey. McCaffrey touched the ball 27 times on Sunday and turned those into four touchdowns and 11 more first downs. He had 106 yards rushing, seven catches for 71 yards, and became the first 49ers player since Terrell Owens in 2000 to account for at least 15 first downs or touchdowns in a game. McCaffrey has 600 yards from scrimmage and seven TDs this season. The only other players to do that in the first four games of the season are Emmitt Smith (1995) and Jim Brown (1958, 1963).

WHAT NEEDS HELP

Special teams. The Niners could have put the game away in the first half had they stopped a fake punt late in the second quarter. Leading 21-3, San Francisco allowed Ezekiel Turner to take a direct snap and convert on fourth-and-2 from the 21. Arizona then drove for a touchdown.

STOCK UP

Purdy is proving he’s more than just a beneficiary of a good offensive system with lots of playmakers. He completed 20 of 21 passes (95.2%) for 283 yards and a TD on Sunday for the best completion percentage in franchise history and fourth best ever for a player with at least 20 attempts in a game.

STOCK DOWN

DT Javon Kinlaw. The 2020 first-round pick had struggled with production and injuries his first three seasons before showing some positive flashes early this season. But Kinlaw once again struggled on run defense against the Cardinals as he was frequently pushed off the ball.

INJURIES

OL Jon Feliciano is in concussion protocol after getting hurt in the game. … RB Elijah Mitchell (knee) and WR Jauan Jennings (shin) are day to day. … WR Deebo Samuel (knee, ribs) is also day to day after being limited the past week by his injuries.

KEY NUMBER

50.9% — The Niners got a first down on 50.9% of the offensive plays they ran for the best rate in a regular-season or playoff game since at least 1991. That doesn’t even include the three first downs gained by penalties. The rate would have been even higher if not for two kneel-downs to run out the clock in each half.