1,100-pound flag.

So, it’s the offense.

The Hawkeyes generated just five first downs, went 1 of 6 on third-down conversions and had just 111 yards of offense. Iowa rushed 14 times for 18 yards. The lone TD came after a fumble recovery that gave the Hawkeyes a first down at Purdue’s 22.

Iowa tried five runs on second/third-down-and-short and came up with minus-1 yard and no first downs.

No, it’s the defense.

Purdue rolled out 243 yards and 14 first downs. The Boilermakers rushed 26 times for 98 yards, including seven for 40 during the TD drive — Robert Marve to Gabe Holmes for a 9-yard TD and a 14-7 lead with 4:43 left in the first half. Marve completed 12 of 15 for 132 yards and the TD. PU converted a third-and-8 from its 27 with a 26-yard Marve pass to wide receiver O.J. Ross to keep that drive alive.

During one 16-yard run, running back Akeem Shavers broke four tackles.

It’s everything.

Purdue kicker Sam McCartney pulled a 20-yarder wide left on an untimed down or the 14-7 would’ve been that much worse for the Hawkeyes.

Iowa is on track to give up 400-plus yards on defense for the fourth straight week.

Kirk Ferentz on the halftime interview: “We’re not tackling much. We’re not doing it offensively. We have GOT to play better.”

He was mad.