From ESPN's Andrew Brandt:
Note that rookie contract are heavily lopsided in first year. Browns have paid bulk of Richardson contract, over $13 million.— Andrew Brandt (@adbrandt) September 18, 2013
Trent Richardson is still playing under the rookie contract - which is scaled per the collective bargaining agreement signed in 2011 - that he signed last year. The former Alabama bruiser was taken with the No. 3 overall pick in the 2012 NFL Draft.
Colts quarterback Andrew Luck was taken with the first overall pick in that same draft.
With such little money invested in, arguably, the two best players on the team, the Colts have financial flexibility both for the short term and "blue chip" pieces to invest in long term.
Though Richardson did not seem to fit in Cleveland's rebuilding plans under first-year team president Joe Banner, that does not mean he magically stopped being the best running back prospect to hit the NFL since Adrian Peterson was drafted No. 1 overall in 2007. And, unlike Peterson when he was taken, the Colts are not investing buckets of cap-killing cash into their new premiere back.