The start of every NFL team’s season comes with a certain inevitability: At some point, adversity will have to be handled and dealt with.

It’s rare, though, when that hardship occurs just before the first day of training camp.

But that is exactly what the 49ers are dealing with after the stunning news that surfaced Saturday about the serious car accident involving head coach Kyle Shanahan, which resulted in severe injuries.

The good news is the injuries aren’t considered life-threatening and that Shanahan is on his road to recovery. Nevertheless, it’s never a small thing when someone suffers multiple fractured ribs, a broken nose and a severe concussion.

Or when the head coach of a team with Super Bowl aspirations will be sidelined for an extended period of training camp, if not beyond.

That is the situation Shanahan and the 49ers are dealing with as they gather for camp at their practice facility in Santa Clara.

Clearly, everyone’s focus is on Shanahan getting better. His well-being trumps everything. But once the NFL train leaves the station, it’s full-bore ahead and can’t afford to slow down for anyone, let alone stop.

Shanahan is as vital to the 49ers’ success as anyone who puts the uniform on, maybe more so. He is recognized as one of the NFL’s best coaches and a brilliant strategist and leader. The foundation for both of those dynamics is built in training camp.

Understandably, Shanahan’s activity will be severely limited for now, which means a valuable 49ers voice and presence will not be heard or felt as it normally would at this critical point in the season.

“Kyle basically is going to be like in the protocol,” 49ers general manager John Lynch said. “Doc [Anthony Saglimbeni] and all the great doctors we have are giving him great care, and we’re going to let you know [his] condition… the doctors dictate how he comes back, when he comes back.”

In the interim, 49ers assistant head coach Chris Foerster will assume some of Shanahan’s duties, but the offensive and defensive operations will primarily be handled by offensive coordinator Klay Kubiak and defensive coordinator Raheem Morris.

Morris is a former head coach, so clearly that will help. While Kubiak is in his second season as the 49ers’ offensive coordinator, it is Shanahan who is in charge of that side of the ball, including playcalling, so Kubiak will assume much more responsibility in Shanahan’s absence.

The 49ers have an experienced, veteran-laden team — especially on offense — and they will lean on all that experience during Shanahan’s recovery.

Clearly, though, this is an early obstacle the 49ers must overcome.