The weekly betting points spread ultimately doesn’t mean much in terms of anything real, unless you’re putting your money on the line, but it is one indicator of how people that know football perceive your team.
Illinois was a 14.5-point underdog on the road against a then-3-5 Purdue team that had also just had the pleasure of losing to Rutgers. The Illini and Boilers are probably the bottom two teams in the conference (maybe throw Minnesota in that mix also? Seriously, the honeymoon has to be over for P.J. Fleck up north) and Vegas had the Illini lagging behind by two touchdowns.