Cleveland Indians superstar Trevor Bauer says he received death threats after getting rocked in his start Monday night ... claiming one fan told him, "I will kill you."
Bauer -- one of the front runners for the AL Cy Young this season -- gave up 10 hits and 8 runs to the White Sox ... and when he returned to the locker room to check his phone, he says it was filled with hate.
"I really hope you and your family die in a car crash," Bauer says one fan wrote.
"I am Chinese.