Opener Ruchira Jayasuriya (47 not out with three fours and a six) and skipper Thushan Amarasuriya (41 not out with four boundaries and a six) was involved in an unbroken second wicket partnership of 95 runs when Royal batted a second time.
Royal who were 6 for 1 overnight in reply to St. Sebastian's 166, fared poorly to make 97 for 9 declared with Danushka Perera (28) and Harith Rajakaruna (21) putting on a face saving 32 runs for the seventh wicket.
St. Sebastian's, too, fared badly in their second turn being 92 for 6 when they declared leaving Royal to make 162 to win.
Scores:
St. Sebastian's 166
(Kanchana Cooray 31, Nuwan Fernando 19, Hemal Perera 39, Dilip
Fernando 24, Sanjeewa Udumalagala 2 for 12, Jehan Mubarak 2 for 36,
Sampath Edirimuni 2 for 14 ) and
92 for 6 declared
(Kanchana Cooray 31, Sunalka Perera 12, Suranga de Silva 23, Sanjeewa
Udamalagala 3 for 14, Jehan Mubarak 2 for 14).
Royal 97 for 9 declared
(Danushka Perera 28, Harith Rajakaruna 21, Nuwan Fernando 2 for 14,
Hemal Perera 2 for 20, Malshan Fernando 3 for 18) and
100 for 1 at close
(Ruchira Jayasuriya not out 47, Thushan Amarasuriya not out 41).