Marion Barber was done in Chicago

Marion Barber's days with the Chicago Bears were numbered from the moment the team demonstrated interest in free-agent running back Michael Bush. So while Barber's retirement announcement Friday was surprising, we already knew he wouldn't be back with the Bears in 2012.

Bush signed a four-year contract Thursday to back up starter Matt Forte, the role the Bears hoped Barber would play more effectively last season. Barber was due to earn $1.9 million in base salary along with a $100,000 workout bonus, so as Brad Biggs of the Chicago Tribune points out, the Bears will save $2 million in cap space once Barber's departure is reported to the league.

In all, Barber and 2009 backup Chester Taylor cost the Bears nearly $10 million over the past two seasons for minimal return. The guess is that Bush will eclipse their production significantly in 2012.