"Buller played really well but the boys kept plugging away and in the end got the reward. We've got another tough game away to Mid Canterbury but this win will do us good after last week's loss to South Canterbury."
The Coast started well but Buller fullback Marty Banks opened the scoring with a penalty after 28 minutes, only for the Coast to reply with a try to Tipoki.
Buller's impressive second five-eighths Pena Nabainivalu reclaimed the lead with a try converted by Banks. With the last kick of the half, Banks made it 13-5.
Samupo reduced the deficit with his first try for the Coast five minutes into the second half but Buller hit back with a try to strong-running centre Trael Joass five minutes later.
With 13 minutes remaining, Tipoki closed the gap to one point. Irish import Semple then kicked the winning penalty.
East Coast 20 (Rua Tipoki 2, Pomare Samupo tries; John Semple con, pen) Buller 18 (Pene Nabainivalu, Trael Joass tries; Marty Banks 2 pens, con). HT: 5-13.