The Boilermakers built their reputation in recent years on their aggressive man-to-man defense, but Purdue had been depending more on its high-scoring offense this season.
The sixth-ranked Boilermakers looked more like coach Matt Painter's teams from previous years while grinding out a 63-40 win Saturday. JaJuan Johnson had 21 points and 10 rebounds to help Purdue win its seventh straight after a three-game skid.
The Boilermakers held Iowa to 30 percent shooting and outrebounded the Hawkeyes 34-29. It was the fewest points Purdue has allowed in Big Ten play and its largest victory margin in a conference game this season.
"The biggest thing in that three-game losing streak was we were getting outrebounded and defensively we weren't as sharp as when we were 14-0," Johnson said. "I think we made those adjustments and we've been a lot better on the glass."
E'Twaun Moore had 11 points and Chris Kramer anchored the defense with four steals for the Boilermakers (21-3, 9-3 Big Ten).
Johnson was held to six points in the first meeting with the Hawkeyes, a 67-56 Purdue win in Iowa City. This time, he had 14 points in the first half.
"He's a matchup problem for everybody," Iowa coach Todd Lickliter said of the athletic 6-10 center. "He's long, he shoots it well, he's patient. I've liked him for a long time."
Johnson was also a factor on defense.
"They are a very, very physical team and they force you to try to drive it, and then when you try to drive it, you got JaJuan back there ready to block it," Lickliter said. "Great game plan, great way to play. It was just really hard for us today."
It wasn't an ideal situation for Iowa, which played at Ohio State on Sunday and at home against Northwestern on Wednesday.
"Traveling, playing three games in a week, playing at Purdue ... you need to be fresh to play them," Lickliter said. "As fresh as you can possibly be."
Cully Payne scored 11 points and Jarryd Cole had 10 for the Hawkeyes (9-17, 3-10). Matt Gatens, Iowa's top scorer this season, finished with three points on 1-of-10 shooting.
Purdue's game against Iowa was sandwiched between matchups with Big Ten leaders Michigan State and Ohio State. The Boilermakers were coming off a 76-64 win at Michigan State on Tuesday.
"The game we have in front of us is the most important game from here on out," Johnson said. "Our team is doing a really good job of buying into that. We just got to be ready to play that day and that's the most important game."
Iowa was trying to build momentum after beating Northwestern 78-65 in its previous game. Instead, the Hawkeyes posted their lowest point total of the season.
Purdue took control early with a 7-0 run during a 5½-minute stretch in the middle of the first half to take a 23-12 lead.
A flurry of steals ignited an 11-0 Purdue surge. Moore finished it in the open court by driving to the paint, taking off on both feet, pulling the ball back, then hesitating briefly in mid-air before dunking hard with his right hand to give Purdue a 34-15 halftime lead.
The Boilermakers shot 50 percent in the first half and held Iowa to 25 percent shooting.
Iowa shot well in the early minutes of the second half and a 3-pointer by Brennan Cougill cut Purdue's lead to 39-28.
Purdue responded quickly. A three-point play by Robbie Hummel highlighted a 12-1 run that gave the Boilermakers a 51-29 lead. The Boilermakers held the Hawkeyes without a field goal for nearly seven minutes during that stretch.
"At this point of the season, teams either go one way or the other," Kramer said. "You can take steps forward, take steps back. We weren't taking any steps back. We came out, we were focused and we were really locked in on the defensive end."