FOX Sports announcer Steve Byrnes died Tuesday of cancer ... just 2 days after NASCAR fans, drivers and crew members paid him an emotional track side tribute.
Byrnes -- one of FOX's leading reporters for its NASCAR coverage -- was diagnosed with head and neck cancer in August of 2013. He was forced to take an indefinite leave from the job last year in October.
FOX and NASCAR teamed with Stand Up to Cancer to dedicate Sunday's race at Bristol Motor Speedway to Steve. Before the race people in the stands ... and crew members on pit road held up signs with Steve's name.
Byrnes is survived by his wife Karen and their 12-year-old son Byrson. He was 56.