Lloris' head collided with the knee of Everton striker Romelu Lukaku in the 77th minute of Sunday's 0-0 draw at Goodison Park, leaving the France captain flat out on the ground.
After lengthy treatment, a groggy Lloris was helped toward the sideline but declined medical advice to be substituted and decided to play on.
Villas-Boas said Lloris "doesn't remember the incident," adding "I made the call to keep him on the pitch because of the signs he was giving . the saves he did after the incident proved that right."
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