CHAMPAIGN, Ill. – To say Michigan State was a long shot on Saturday would be generous. Down eight players because of suspension and a handful more because of injury, the Spartans were facing No. 16 Illinois at Memorial Stadium with no momentum, the home team sitting atop the Big Ten West. Instead of crumbling, though, Michigan State responded with arguably its most spirited effort of the season, upsetting Illinois, 23-15, in front of 56,092 stunned Fighting Illini fans. The Michigan State defense, a unit that has struggled all season and was down three starters, didn’t allow Illinois to conver…