Trevor Wright poured in 28 points and Chris Washington added 17 to help the Hilton Head High boys to a 66-63 win over Battery Creek on Tuesday.
The Seahawks led by one at halftime but stretched the margin to eight by the end of the third quarter and went 8-for-11 from the foul line in the final period to seal it.
Davis Molloy scored 14 points to join Wright and Washington in double digits.
DeNarol Brown scored 16 points, JaQuan Burton added 14, and Brandon Wilson had 11 for the Dolphins.
The Seahawks (4-3) face Silverdale Academy (Tenn.) at 8:30 p.m. Thursday in the first round of the Seahawk Holiday Classic, which continues through Saturday at Hilton Head High.
The Dolphins (4-7) play in the Bobcat Classic at Bluffton from Dec. 28-30.