Colts vs Titans: Shaquille Leonard leaves his season debut with concussion

Indianapolis Colts linebacker Shaquille Leonard was taken to the locker room Sunday after being inadvertently hit by teammate Zaire Franklin in the second quarter. He was ruled out with a concussion.

The Tennessee Titans scored on the play, taking a 24-3 lead.

Leonard, in his fifth year, made his season debut Sunday after missing the first three weeks following summer back surgery.

Leonard was in on 2 tackles before leaving the game.

What are the steps for returning to play from the NFL concussion protocol?

What are the steps for returning to play?

There are five steps to complete with the decision to return to full participation confirmed by the Independent Neurological Consultant, who is an independent neurotrauma doctor.

All decisions for returning to full participation need to be confirmed by the Independent Neurological Consultant, who is an independent neurotrauma doctor.

Phase 1: Symptom-limited activity

The player is prescribed rest and to avoid activities that aggravate symptoms. Limited stretching and balance training can be introduced, progressing to light aerobic exercise, under athletic training staff supervision. If the player doesn't have an increase in symptoms and doesn't demonstrate signs of a concussion during a neurological examination, they are cleared for the next phase.

Phase 2: Aerobic exercise

Players begin graduated cardiovascular exercise and dynamic stretching and balancing training under the supervision of team staff. If the player can engage in cardiovascular exercise without an increase or aggravation of symptoms, they move on to next phase.

Phase 3: Football-specific exercise

Continued supervised cardiovascular exercises that are increased and may simulate sport-specific activities. Supervised strength training is introduced.

Phase 4: Non-contact training drills

The player continues cardiovascular, strength and balance training, adding team-based, sports-specific exercises and participation in non-contact activities.

Phase 5: Full football activity/clearance

The player is cleared by the team doctor for full football activity. The player must be examined by the independent neurological consultant assigned to his team. If the consultant agrees with the team physician that the player’s concussion has been resolved, the player can participate in practice and contact without restriction.

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