SANTA CLARA, Calif. – The 49ers were without star running back Christian McCaffrey for Monday night’s game against the Jets, but it didn’t matter.

McCaffrey was surprisingly not used before the game. The 28-year-old was struggling with a calf strain that cost him four weeks of training camp, but he was back in training and should play.

Even without McCaffrey, the 49ers beat the Jets 32-19. The 49ers gained 180 yards rushing, including 147 yards by reserve player Jordan Mason.

“They beat us up front, plain and simple,” said Jets coach Robert Saleh.

The 49ers announced this week that McCaffrey had a calf/Achilles injury, which caused some confusion. But McCaffrey told reporters Friday that his calf feels “a lot better” and his Achilles is “no concern for me.”

McCaffrey said he had no doubts he would play against the Jets. Mason made his first career start in place of McCaffrey, the reigning AP Offensive Player of the Year and rushing champion.

McCaffrey had 1,459 rushing yards on 272 carries and 14 rushing touchdowns. He also had 564 receiving yards and seven receiving touchdowns.

The Jets have talked all week about preparing for McCaffrey. While the 49ers have plenty of talented offensive players, McCaffrey is San Francisco’s undisputed top weapon.

There was a strange sequence in the second quarter where CB Sauce Gardner was on the sideline for nine plays. Gardner was on the sideline with his helmet on and the Jets said it was not injury related. After the game, both Saleh and Gardner said he was trying to catch his breath, which seemed like a strange explanation.

“I made a tackle and just had to catch my breath,” Gardner said. “When I felt like I was good, I went back on the field.”

CB Michael Carter II left the game in the fourth quarter with an ankle injury, just days after the Jets signed him to a three-year contract extension. Saleh said Carter could have returned to the game, but the Jets were cautious. Saleh revealed that Carter’s ankle injury during training camp was a high ankle sprain, an injury that can linger for a long time.

“It’s just something he has to deal with all year,” Saleh said.

The Jets elevated OL Jake Hanson and LB Sam Eguavoen from the practice squad to the active roster before Monday night’s game. They also promoted TE Anthony Firkser and DE Jalyn Holmes from the practice squad. LB Zaire Barnes was placed on the injured list, meaning he will miss at least four games. The Jets also elevated RB Kene Nwangwu to the practice squad. … The nonactive Jets were RB Israel Abanikanda, CB Jarrick Bernard-Converse, DE Eric Watts, OT Max Mitchell, OT Carter Warren, TE Brenden Bates and DT Leonard Taylor. … Frank Gore, who played for the Jets in 2020, was an honorary captain for the 49ers.