SANTA CLARA, Calif. -- Moments after a collision with linebacker Donavin Newsom that left him motionless on the field Tuesday, San Francisco 49ers safety Chanceller James was so overcome with emotion that he walked away from the scene and could barely bring himself to look at his teammate.

James, of course, did not intend to hit Newsom, and the collision was accidental as both tried to make a play on a pass that had been thrown over the middle. In that moment, James was overcome with the thought that it was his fault.

"Obviously, you don't want to feel responsible, but it's not his fault," quarterback Brian Hoyer said. "It's football. They're both going for the football and it was an unfortunate event. I'm sure there's, I guess we call it maybe survivor's remorse or whatever, but you've just got to emphasize to those guys it wasn't [his fault]. It's not like he’s trying to go take out a receiver and knocked that guy out. He took his own guy out. It wasn't anything that was dirty or uncalled for, it's just two guys going and playing football. Unfortunately, in our sport, things like that, they happen sometimes."

At this point in their careers, most players have at least witnessed something like this. 49ers coach Kyle Shanahan said he has seen similar plays numerous times and been fortunate that none of the resulting injuries were as serious as first feared.

Newsom was taken to Stanford Medical Center in an ambulance about 12 minutes after the collision. Later Tuesday, the Niners confirmed that Newsom suffered a concussion but that there was no cervical spinal damage. Considering the many possibilities, it was relatively good news.

After Newsom suffered the injury, Shanahan immediately canceled the rest of the practice, but now his team must collect itself and return to practice on Wednesday before playing the Kansas City Chiefs in Friday's preseason opener. The news that Newsom is OK should make that an easier proposition, but as Shanahan pointed out, such moments can bring back into focus what can happen to these players every time they step on the field.

"We're playing football," Shanahan said. "It's part of the sport. Sometimes things like that happen, and you pray for the best, you hope for the best. It is part of the game. That's why I can't have any more respect than I do for NFL players and college players, people who played the game, because it is risky like that."

As with the risks of chronic traumatic encephalopathy, or CTE, that players have talked about recently, 49ers players say they understand the possibilities when they play but also aren't immune to letting their imaginations wander when something like Newsom's injury happens.

"These things happen and you hate to see it," safety Eric Reid said. "I think everybody pauses for a minute just to get their thoughts together and to pray for whoever is injured, especially in a situation like this. But they don't end the game. It sucks but you have got to kind of move on quickly. And then when you have time after the game, or for us [today] after practice, just go check on that guy and make sure he's OK."

Reid recalled injuring linebacker NaVorro Bowman on a similar play during his rookie season and some of the guilt he carried with him. At the time, he leaned on his teammates to remind him that it was accidental and everybody came out of it OK.

Hoyer also brought up witnessing a quad injury at one of his previous stops.

"You hear him screaming and they have to bring out the cart for him," Hoyer said. "And, same thing, you say a little prayer, you wish him good luck and then you get back to business. As cold as that sounds, the moment you start to think about, 'Oh geez, what if that happens to me?' I think you put yourself in a more vulnerable position. So you just go back out just as aggressively the next time and you play just as fast as you normally would, because I think the moment you don't, that's when you put yourself in an even worse position."

Shanahan said he doesn't intend to make any changes to how the Niners practice. It's been a physical camp, but something like what happened to Newsom, while unfortunate, is part of the game.

"I don't think that play was from being too physical," Shanahan said. "That's getting hit at the exact spot at the right time. I think it was their own guys too, from what I saw. From my view it was two defensive players colliding with each other. ... But no, you've got to practice football, but you've got to be as smart as you can too. That's something we work at, but no, that's not going to change how we practice."