Alama Ieremia has resigned as head coach of Manu Samoa, after the team fell short of automatic qualification for the 2019 Rugby World Cup.
The Manu lost all four tests in the June-July international window, including defeats to Tonga and Fiji in the Pacific Nations Cup.
In a statement, Ieremia said the losses had proven costly for everyone, and he must take full responsibility for the results.
"It is with a very heavy heart that I have decided to stand down," he said.
"I believe my decision today is the best one for our beloved Manu Samoa team."
Ieremia said he was proud of the team's development, saying there was a strong foundation for it to move towards great things in the future.
Samoa Rugby Union chief executive Vincent Fepuleai saluted Ieremia's decision.
"The most recent performances ... and the heartbreaking disappointment of not yet qualifying for Rugby World Cup 2019 have forced us to ask ourselves some challenging questions," he said.
"His decision today is a testament to his ability to put the team first above his own interests and I commend him for that."
Samoa still have two chances to qualify for the World Cup; when they face a home-and-away playoff against a European qualifier next year, with the winner advancing to a final repachage tournament.