Washburn reversed the result from his matchup with New York starter Darrell Rasner last Sunday, when Rasner picked up his first win by throwing 5 2/3 scoreless innings.
This time it was Washburn (3-3) who did the blanking by scattering six hits over eight innings. J.J. Putz picked up his eighth save.
Rasner (1-2) allowed three runs on seven hits over five innings.
Johjima's shot to left off Rasner in the fourth scored Adaian Beltre and gave Seattle its 3-0 lead.