Rudi Johnson, a former running back for the Cincinnati Bengals, has died at the age of 45.
A cause of death is not yet known but according to TMZ, the 45-year-old had been struggling with mental health issues.
The report adds that he feared he had CTE, the brain disease common in former NFL players that can only be diagnosed after someone has died.
Johnson would have turned 46 next week.
He was picked by the Bengals out of Auburn University in the fourth round of the 2001 NFL Draft and played eight seasons.
After a slow first two years, he exploded in his third by rushing for 957 yards and scoring nine touchdowns.
Rudi Johnson, a former running back for the Cincinnati Bengals, has died at the age of 45
Johnson was picked by the Bengals out of Auburn in the fourth round of the 2001 NFL Draft
In the following three years, he became a dominant force and rushed for over 4,000 yards and 36 touchdowns.
Johnson was released by the Bengals in 2008 and signed with the Detroit Lions, where he played the final season of his career.
TMZ reported that Johnson 'had been recently struggling with mental health issues and the possible effects of CTE that he could not overcome.
'The family source says prior to his death, Johnson was doing everything he could to help people on and off the field... and that's what mattered most to him."