His statline looks good because the Bucs defense wore down in the 4th quarter. He wasn't even average before that.
At least he was good enough to take advantage of that. If he can come in and offer relief and some production when Addai needs a rest, it's certainly a good thing for the Colts although Addai deserves a lot of credit for carrying the load before going down as people were doubting how effective he could be with Rhodes departure.