An autopsy released in August found that the 27-year-old had fentanyl, oxycodone and ethanol in his system when he died. A medical examiner in Texas determined Skaggs choked to death on his own vomit while under the influence of alcohol and the powerful painkillers.
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The fentanyl drew the attention of federal investigators, a source with knowledge of the investigation told ESPN. One senior DEA official said the agency typically gets involved in fentanyl cases in an effort to track down the source of the drug.
Skaggs was found dead in his hotel room in the Dallas area July 1 before the start of what was supposed to be a four-game series against the Texas Rangers. The first game was postponed.
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The Skaggs' family released a statement after the contents of the autopsy report were made public:
"We are heartbroken to learn that the passing of our beloved Tyler was the result of a combination of dangerous drugs and alcohol. That is completely out of character for someone who worked so hard to become a Major League Baseball player and had a very promising future in the game he loved so much."
The family also indicated that they believe an employee of the Angels was involved in some way with his death, possibly by supplying him with the drugs. They have hired an attorney to help investigate his death.
"We are grateful for the work of the detectives in the Southlake Police Department and their ongoing investigation into the circumstances surrounding Tyler's death. We were shocked to learn that it may involve an employee of the Los Angeles Angels. We will not rest until we learn the truth about how Tyler came into possession of these narcotics, including who supplied them. To that end, we have hired Texas attorney Rusty Hardin to assist us."
The Angels organization issued a statement on Twitter:
"Tyler was and always will be a beloved member of the Angels Family and we are deeply saddened to learn what caused this tragic death," the team wrote.
"Angels Baseball has provided our full cooperation and assistance to the Southlake Police as they conduct their investigation."
The team's general manager, Billy Eppler, later spoke at a press conference, saying the organization could not comment on the facts surrounding Skaggs' death until police in Texas conclude their investigation. He said the team is fully cooperating with that investigation.
"Everyone's searching for facts," Eppler said. "Everyone with the organization wants facts."
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Skaggs was born in the Woodland Hills neighborhood of Los Angeles and went to high school in Santa Monica. Though his high school was just across town from Dodger Stadium, he grew up rooting for the Angels.
Skaggs was drafted by the Angels in 2009 out of high school but was then traded to the Arizona Diamondbacks before making his Major League Baseball debut. He returned to the Angels in a trade in 2013.
Skaggs, who would have turned 28 on July 13, had been a regular in the Angels' starting rotation since late 2016, when he returned from Tommy John surgery.
He struggled with injuries repeatedly over the previous three seasons but persevered to become a valuable starter in Los Angeles' injury-plagued rotation.
Skaggs started a career-high 24 games last season, going 8-10 with a 4.02 ERA. He missed playing time in April this season with a sprained ankle but came back strong.
The Associated Press contributed to this report.