The Mod Squad/The Loser (1971)
Julie's former neighbor has fallen victim to several 'accidents', and when he's almost killed riding his motorcycle, the Squad goes to work, trying to find out who's behind the accidents and why. When Linc discovers the truth behind the mishaps--the man himself paid someone to kill him--he finds his own life in danger.
This is the second episode of the series entitled "The Loser". The other episode was the second season finale.