Gunther Cunningham has admitted that the Detroit Lions are having problems with defence.
The Lions lost to the Houston Texans last Thursday, allowing the visitors to come from behind late in the fourth quarter.
The NFC North side's defensive coordinator told the club's website: "It's amazing to me that we couldn't stop them. We had two or three opportunities and you're damned if you do and you're damned if you don't.
"We cannot get a turnover at the right time now. That's probably more frustrating than reads or than anything else we've done.
"Hopefully it'll get better as we go. And I kept feeling the balls coming out, and it was, we've had some sack strips and we still can't get it. That's what we need in a game like that and we didn't get it."
The Lions are 4-7 this season, and sit bottom of the NFC North.