A Washington state man will be tried in a 1989 murder after his co-worker swiped his discarded Coke can and helped detectives solve the case, according to reports.

Timothy Bass, 51, is set to go on trial for the rape and murder of 18-year-old Amanda “Mandy” Stavik, who went missing while on a jog near her home in Acme, the Washington Post reported.

The teen’s body was found three days after her disappearance, but her killer remained a mystery for nearly three decades.

The break in the cold case came in August 2017 when Bass’ colleague at Franz Bakery Outlet learned he was a suspect in the murder.

The bakery co-worker — whose identity hasn’t been released — said she came up with the idea because she felt a moral duty to help with the investigation, according to the Washington Post.

She reportedly secretly grabbed Bass’ Coke can and plastic cup after he finished his lunch — then gave the evidence to detectives, who sent it to a crime lab.

The results indicated that Bass’ DNA was a one-in-11 quadrillion match to the DNA recovered from the crime scene.

Bass’ lawyer argued that the evidence shouldn’t be used at his trial because it was the result of an illegal search. But a judge ruled that the search didn’t violate Bass’ rights because the co-worker wasn’t acting as an agent of law enforcement.

The trial is scheduled to begin in April.