Aaron White had 18 points and 10 rebounds, Melsahn Basabe added 16 points with 10 boards and No. 20 Iowa routed Northwestern 93-67 Thursday night.
Devyn Marble scored 15 points for the Hawkeyes, who never trailed despite McCaffery's absence. He was suspended one game by the Big Ten for an outburst directed at officials during last weekend's loss at Wisconsin.
Iowa (13-3, 2-1 Big Ten) opened the game on a 10-0 run and never looked back. The Hawkeyes led by double digits the entire second half, improving to 10-0 at home.
"We really approached this week with great maturity and great focus. I thought they executed the game plan very well," said Iowa assistant Kirk Speraw, who handled head coaching duties for McCaffery. "I thought they did a great job defending them."
JerShon Cobb had 18 points to lead Northwestern. The Wildcats (7-9, 0-3) were outrebounded 41-28 and let the Hawkeyes shoot 8 of 14 from 3-point range.
This was the first time Iowa played without McCaffery on the bench since he took over as coach in 2010.
The Hawkeyes looked just fine playing for Speraw.
Iowa went through a stretch of sluggishness that allowed Northwestern to get within four after its 10-0 spurt at the start. But back-to-back 3s from Mike Gesell and Jarrod Uthoff put the Hawkeyes back ahead 26-15.
White, who scored his first 10 points at the free throw line, finished a fast break with a dunk that gave Iowa a 41-26 halftime lead.
"I thought they were fighting early in the game. We forced them into some turnovers," Northwestern coach Chris Collins said. "I thought they wore us down as the game wore on."
Basabe -- who committed to McCaffery while he was at Siena and followed him to Iowa -- became the 42nd player in school history with at least 1,000 career points late in the first half. His tip-in of a miss by White made it 55-35 with 15:31 left.
Adam Woodbury matched a season high with 10 points for Iowa, which shot 57 percent from the floor and cracked 90 points for the fifth time.
"Business as usual. [McCaffery] went over the game plan with us. Just a different voice, but they all have the same intensity, the same mindset, the same focus," White said of the Iowa coaching staff.
Northwestern had its share of promising moments in non-conference play, winning three straight before a one-point loss to crosstown rival DePaul. But the Wildcats have been overmatched in Collins' first Big Ten campaign.
Northwestern has lost all three league games by at least 23 points.
Drew Crawford scored 12 points for the Wildcats, which had just four assists.
"We were outsized at every position," Collins said. "They're as good as it gets in our conference at pushing the ball and scoring in transition."
The Hawkeyes will get McCaffery back for Sunday's road game at No. 3 Ohio State. They'll probably need him for that one, with the Buckeyes coming off their first loss of the season in overtime at No. 5 Michigan State.
Iowa is 0-2 on the road, though both losses came against ranked opponents Iowa State and Wisconsin by just seven combined points.
"That's one of the better teams in the country, obviously. But it's just another step in our journey down the Big Ten schedule," Speraw said about Ohio State.