A source within the Colts' organization said that injuries at running back forced the discussion to bring Rainey in for a tryout. Though Rainey's talent and 4.3 speed in the 40-yard dash were undeniable to the Indianapolis front office, his checkered past was the reason for the lack of suitors after his departure from Pittsburgh.
As a result, the Colts investigated Rainey's situation. According to the source, they found a guy who is clean off the field -- he doesn't drink or smoke -- and came up in a tough circumstance; he behaved badly and the charge eventually was dropped.
Ultimately, the Colts are giving Rainey a second chance and a clean slate. That's what they believe the running back deserves. In addition, on the team's end, there essentially is no financial risk in signing Rainey. It's a move similar to what other contending teams make as Indianapolis looks to maintain its lead in the AFC South.