While Rivers stayed on the ground, sprawled out on his back, Jordan faked chest compressions on Rivers – a callback to Paul doing the same thing after Paul Pierce missed a dunk earlier this season.Once Rivers headed to the bench, he passed the team’s tests, Clippers coach Doc Rivers said. However, while sitting down near the end of the third quarter, he wrapped his head in a towel and, later, literally tried to shake things off.He then went back in the game in the fourth quarter.“That blow, obviously had a delayed effect. He passed all the tests,” Doc Rivers said. “And, right when he went on the floor, you knew something wasn’t wrong. When I saw him grab his head because of the noise, you knew something was going on.”Austin Rivers played less than a minute in the fourth before being helped off the court for what the team called an “evaluation.” He was diagnosed with what the team called a “mild concussion.”By suffering a concussion, Rivers now enters the league’s concussion protocol, something the NBA adopted in 2011.Earlier that season, Paul was stretchered off the court after suffering a concussion in a game between the New Orleans Hornets and the Cleveland Cavaliers. While Paul was on the ground, announcers for that game assumed Paul was trying to sneak extra rest.Again, one of the biggest challenges with concussion policy is that it must be flexible because of the variance in the injury.“Understanding that concussions are diverse injuries that may have significant long-term consequences, the NBA Concussion Policy is designed to maximize the health and safety of NBA players by providing a framework of education and clinical management that best reflects the current scientific understanding of the injury,” the NBA’s policy reads.Boston’s Al Horford missed nine games with a “mild” concussion earlier this season. The Lakers’ Larry Nance Jr. missed just one game with a concussion in early November.According to the NBA, “if a player is suspected of having a concussion, or exhibits the signs or symptoms of concussion, he will be removed from participation by either a team physician or the player’s team athletic trainer and undergo evaluation in a quiet, distraction-free environment conducive to conducting a neurological evaluation.”The league’s concussion policy, which emphasizes education to players, coaches and medical staff, also provides strict guidelines for a player’s return once they enter the protocol.Before Rivers can return to action, he must be symptom free and pass through a graduated set of physical tests – riding a stationary bike, jogging, agility drills and non-contact team drills. He must be cleared by a physician and have his case discussed with the head of the NBA’s concussion program.As Paul remembered the night he was stretchered out, he mentioned the blow he took Saturday night as well.The difference between the two?“You don’t know until it hits you,” he said. LOS ANGELES >> As Chris Paul walked out of the interview room after scoring 20 points and handing out 20 assists without committing a single turnover – something that’s never been done since those statistics have been tabulated – he pointed to the souvenir he was taking home.Behind his right ear, a lump had already formed, the result of a collision with a man a foot taller and 80-pounds heavier.Paul was lucky that it was a visible bump and not a more serious, hidden problem – the kind of internal injury that doctors and scientists are still trying to understand.Austin Rivers wasn’t as lucky. Newsroom GuidelinesNews TipsContact UsReport an Error The Clippers guard got struck with an inadvertent elbow from New Orleans’ Terrance Jones, sending him down to the court.As his teammates gathered around and tried to help him up, Rivers kept his arms over his face, forcing the Clippers to take a timeout.“It’s always tough, scary,” DeAndre Jordan said. “I was just happy that he was able to get up and walk out on his own two feet.”Rivers was eventually diagnosed with a concussion. At a minimum, he won’t play for the Clippers on Monday night.Before that conclusion was reached, though, a number of things illustrating the challenges of dealing with internal injuries occurred.