SANTA CLARA – The bad news came Wednesday morning.

But one day later, 49ers coach Kyle Shanahan said he felt fortunate that the outlooks for defensive end Nick Bosa and cornerback Jason Verrett were not altogether gloomy.

Bosa and Verrett sustained ankle injuries in practice that could keep each player out for approximately four weeks. Shanahan said he hopes that both will be available for Week 1 of the regular season on Sept. 8 against the Tampa Bay Buccaneers.

Shanahan said Bosa was lucky to avoid a season-ending knee injury when a 300-pound-plus teammate landed on his lower leg. And, initially, the 49ers thought Verrett’s injury was significant.

“I think he was in a little dark place yesterday morning because we thought it was going to be worse than it was,” Shanahan said of Verrett. “The day ended up positive.”

Bosa and Verrett are not the only 49ers players whose availabilities for Week 1 are in question. Running back Jerick McKinnon, nickel back K’Waun Williams and center Weston Richburg will be sidelined for multiple weeks.

McKinnon had a platelet-rich plasma (PRP) treatment after experiencing soreness in his knee after two days of returning to practice. He’ll have two weeks to recover after the treatment, then 18 days before Week 1 of the regular season, Shanahan said.

“If he’s ready, that would be great,” Shanahan said. “If not, we’ll be patient with him.”

Williams underwent an arthroscopic procedure, and Richburg remains on the physically unable to perform list after offseason surgery.

 

Bosa and Verrett have experienced their share of injuries in the past, which makes the injuries they sustained in practice even more difficult to handle.

“You’re dealing with two guys that it means more to them to play football and be successful than you could ever imagine,” Shanahan said. “It’s their livelihoods. It’s everything they do.”

Bosa was one of the standouts of training camp through the team’s first 10 practices. The 49ers selected him No. 2 overall in the draft despite him playing in just 2 ½ games in his final college season before sustaining a core muscle injury.

“I’ve been around one of the most physical rookies I’ve been around, as far as playing the run and playing the pass,” Shanahan said. “He gets after it. He’s tough as can-be.”

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Verrett has appeared in just 25 games since entering the 2014 as a first-round draft pick of the Chargers. He missed all of last season with an Achilles tear.

“What Jason’s been through these last few years,” Shanahan said. “Everybody knows how good of a corner he is – not just us, everyone does. And for him to not be able to go out there and show that has got to be frustrating for him.”