He was airlifted by the Air Force to a private hospital in Colombo and underwent a CT scan, said Sri Lanka Cricket secretary Mohan de Silva.
His condition is not serious, said the secretary, quoting doctors.
Kaushal was struck by a ball that was hit by Dinesh Chandimal while fielding at short leg, said manager Charith Senanayake.
He scored a century in the game that was for the Sri Lanka pool that takes part in a series with England.