SANTA CLARA – Quarterback Jimmy Garoppolo called an audible during the 49ers’ bye week.

“I know he had plans to go home and see his parents, and he ended up staying here and he was up at the office a lot, relaxing and evaluating what he’s done so far,” 49ers coach Kyle Shanahan said Thursday.

The 49ers went 3-0 before having an early bye in Week 4. They returned for scheduled practices at the team’s training facility on Monday and Tuesday, followed by a day off Wednesday. The club reported back for practice Thursday.

Garoppolo and some of his teammates remained in the South Bay even after Shanahan dismissed the team after practice last Tuesday. Garoppolo said it was “weird” to have a bye week so early. He opted to remain close to work during his time off rather than spend the time with his family in suburban Chicago.

“It’s not the best weather in Chicago I heard, so, it never hurts to stay here in this California weather,” Garoppolo said. “I’ve never had one (bye week) this early before, so I thought it was the right thing to do.

“I ended up staying here and everything, just to try and keep this thing going.”

The 49ers are the only unbeaten team in the NFC. They will put that record on the line Monday night against the Cleveland Browns (2-2) at Levi’s Stadium.

“Every week, we try not to put any more emphasis on one or the other, but we just try and go 1-0 every week,” Garoppolo said. “This week’s no different. Got a good opponent coming in, going to give us a lot of challenges, you know, the explosive offense and everything, so it’ll be good for us.

“It’ll be exciting, a lot of juice. Levi’s was rocking last time when the Steelers came and wouldn’t expect anything less from the Faithful. It’ll be a fun atmosphere, that’s for sure.”

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Garoppolo got a head start on preparing for the Browns’ defense with the extra time in the building last week. Shanahan said he did not have much one-on-one time with Garoppolo during the bye, joking that they need a break from each other.

In studying the Browns, Garoppolo said the 49ers will face a stiff challenge against a strong defensive line, headlined by Myles Garrett, the No. 1 overall pick of the 2017 draft. After registering 13.5 sacks last season, Garrett already has six sacks in four games this season.

“It starts up front,” Garoppolo said. They’re very talented, have some guys up front who can just flat out go. And then across the board, their scheme overall, it’s pretty complicated, so it’ll be a good challenge for us.”