Michigan State is favored by 17 in the rivalry game against Michigan on Saturday, according to VegasInsider.com.
The line opened at 15.5 Sunday afternoon but quickly jumped to 17.
The Spartans are 6-1 and ranked No. 8 in the Associated Press poll. Michigan is 3-4. Saturday's game at Spartan Stadium begins at 3:30 p.m. and will be televised by ABC.
Michigan State has won five of its last six games against Michigan.