CHAMPAIGN—D.J. Richardson scored 18 points and Illinois opened up a big first-half lead that buried Purdue 79-59 on Wednesday night.The win was the third straight for Illinois (18-8, 5-7 Big Ten), which is clawing its way back into the postseason picture. The other wins were resume-builders over No. 1 Indiana and then-No. 18 Minnesota.A dunk by Tyler Griffey with 8:46 remaining put Illinois up 64-46. The margin was too much for a Boilermakers team that had already tried to dig out of a 16-point first-half hole.Griffey scored 12 points and Joseph Bertrand had a career-high 12 rebounds.Terone Johnson led Purdue (12-13, 5-7) with 18 points. Boilermakers coach Matt Painter was ejected for arguing with officials with just over eight minutes to play.