Joe Staley never saw the illegal hit on Marquise Goodwin. “I just heard it,” the 49ers left tackle said Sunday. The sickening thunder of a helmet-to-helmet blow was enough for Staley go sprinting in Goodwin’s direction. And as soon as he saw the 49ers receiver laying on the ground, Staley began waving frantically for medical assistance. “I saw his arms kind of seizing up,” Staley said. “His eyes were closed. It was just scary.” By the end of the game, Goodwin was back from the hospital, where his concussion was evaluated, and smiling again in the 49ers locker room. He tweeted that he had “no soreness, no headache, no memory loss, no anything.” But the lingering image from a 34-13 victory over the Los Angeles Rams was the way the 49ers responded to the vicious blow that knocked him out. You want to understand what John Lynch and Kyle Shanahan built this season? You want to get a feel for what the 49ers locker room is like? You want to understand the direction of this franchise? Consider how the players responded after the Rams made the mistake of messing with Marquise Goodwin. Jimmy Garoppolo’s first reaction was anger. “Unbelievable that the safety did that,” the 49ers quarterback said. “It’s just not good. It’s not good for our sport. It’s not good for anybody. It’s a dirty play.” Shanahan wouldn’t go so far as to call it dirty. It’s possible that defensive back Blake Countess went low on his tackle in an attempt to avoid a helmet collision. “I’m sure the guy didn’t have the intent to do that,” the coach said. Either way, Shanahan made note of the fiery resolve in the 49ers’ huddle after Goodwin was carted off the field.