Los Angeles Rams' Bobby Wagner, Takkarist McKinley handle fan who gets onto field during Monday N...

SANTA CLARA, Calif. -- Shortly before halftime of the Los Angeles Rams' 24-9 Monday night loss to the San Francisco 49ers, a fan ran across the field with what appeared to be a device letting out pink smoke.

As the fan sprinted toward the Rams sideline, Bobby Wagner said he noticed that security at Levi's Stadium could use some help.

Rams linebacker Takkarist McKinley came toward the person then Wagner stepped in and laid him out with a big hit.

"That's not making a play," Wagner said. "That's just keeping it safe. You don't know what that fan got or what they're doing. You see it all the time, and we don't know what they're carrying in their pockets. It's whatever that little smoke stuff is, but that s--- could be dangerous.

"One of the guys on the other side, it looked like he got hurt, and security looked like he was struggling, so I was frustrated, so I took it out on him."

The collision left a noticeable mark on the field near the 40-yard line.

"I saw Bobby Wagner take somebody out," 49ers coach Kyle Shanahan said. "That was kind of cool to see."

A fan also ran onto the field with a device letting out pink smoke earlier in Monday night's game but was stopped by security.