WEST LAFAYETTE, Ind. -- When 7-foot-2 center Isaac Haas and 6-foot-8 power forward Caleb Swanigan are creating havoc on the same night, No. 21 Purdue is extremely good and extremely difficult to beat.

Toss in 46.7 percent 3-point shooting and 20 of 22 from the free throw line, and an opponent's task is close to impossible, especially in Mackey Arena.

Haas scored 24 points and grabbed six rebounds, and Swanigan added 22 points and 10 rebounds as Purdue beat Illinois 91-68 on Tuesday night in Mackey Arena.

"With that team, you kind of have to pick your poison," Illinois coach John Groce said. "They have the two great post players, and then they surround them with good shooters. We let them get loose from 3 early, and the 3-point line got them out front and eventually into a double-digit lead."

Haas and Swanigan were a combined 16 of 27 from the field and 13 of 14 from the free throw line.

Purdue (15-4, 4-2 Big Ten) established a 14-point halftime lead before dominating the final 20 minutes, building a 27-point lead on a Haas dunk with 8:26 remaining.

"We have to have balance, and we did that tonight," Purdue coach Matt Painter said. "When Isaac got the ball that deep like he did tonight, that's hard to stop. When Isaac is good and efficient, it really puts the other team in a bind."

The Boilermakers, who lead the all-time series 100-87, also got 14 points from Carsen Edwards, 11 from Vince Edwards and 10 from P.J. Thompson.

Illinois (12-7, 2-4) got 15 points from Maverick Morgan and 12 from Malcolm Hill but could not contend with the 7-foot-2 Haas and the 6-8 Swanigan.

Purdue made nine of its first 14 field-goal attempts, including 5 of 7 from 3-point range, built a 19-5 lead with 13:01 remaining in the first half and coasted to a 44-30 advantage through 20 minutes.

"I don't think the 3-point success made the game easy, but it gave us confidence and definitely let us get our heads up," Haas said. "We were getting open shots. It wasn't like we were taking contested one on one shots. We were moving the ball and getting open looks."

Swanigan said the Illinois defensive philosophy opened up scoring paths to the basket.

"It was Illinois' game plan not to double," Swanigan said. "You could hear coach Groce telling them to pressure the ball. That was their game plan, and we just had success with it."

Carsen Edwards had 12 first-half points for the Boilermakers, and Haas added 11, helping Purdue shoot 60 percent.

Illinois got eight each from Hill and Morgan during the opening half when the Illini shot only 36.1 percent, including 2 of 8 from beyond the arc.

Purdue outrebounded Illinois 20-13 in the first half, but was guilty of five turnovers, three more than the Illini.

Overall, the Boilermakers recorded a 35-28 rebounding advantage while shooting 60.4 percent from the floor. The Illini shot 40.3 percent.

NOTE: Illinois fell to 0-4 against Top 25 competition this season. ... The Illini won last season's only regular-season meeting (84-70 on Jan. 10 in Champaign) before Purdue blasted Illinois 89-58 in the Big Ten tournament quarterfinals. ... G Malcolm Hill scored 30 points in Illinois' regular-season victory against the Boilermakers. ... Purdue scored at least 75 points for the 11th time in the past 12 games, with a 66-55 win over Wisconsin the only game in which it failed to reach 75. ... In conference games only, the Boilermakers lead the Big Ten in free-throw percentage at 85.7 percent (108 of 126).