Lions defensive coordinator Gunther Cunningham had the best view of anyone during Sunday night's 27-19 loss in San Francisco and came away from that game with the same impression of the Lions' tackling in that game as most everyone else who watched it.
"We were bad," Cunningham told Detroitlions.com.
Cunningham said he was especially disappointed in the tackling because they'd tackled so well the week prior against the Rams and he thought they'd prepared well all week for the 49ers.
"I think the emotions of the game got the best of some of our players," he said.
"All the key progressions and all the tackling progressions we had made going into the first game seemed to fall apart. Guys were trying too hard. They were trying to make plays by not following the system and that caused some bad angles for some of our other guys."
The 49ers gashed the Lions for seven running plays of more than 10 yards and averaged 5.5 yards per carry in the game. He said after watching the film he didn't recognize the team he'd watched in practice the week prior to Sunday's game.
"You see the adjustments players have to make because one of their teammates did the wrong thing on a play. They have to react back and tackling a guy like Frank Gore makes it really hard. That's what happened in the game, in my opinion," Cunningham said.
"I thought the coaches did a great job and the players did a great job in preparation and somehow one or two guys took it on themselves to do some other things."
Cunningham said Sunday's breakdowns on defense were more mental than physical.
"I thought (linebackers coach) Matt Burke coached as well as I've seen him coach since I've been with him," he said. "All of the linebackers were tuned in. The plays they ran were exactly the same plays we practiced. So, I guess Sunday night game and a big game … some of us didn't handle it very well."
Cunningham also spoke to Detroitlions.com on a number of other topics:
On the mounting injury concerns in the secondary:
"I talked to Scott (Linehan) about it. They've had their own share of injuries on offense through the years that he and I have been together.
"You can't ever use it as an excuse, but my God, every time I turn around another one goes down. I'd like to see a bus stop out front and unload about four or five guys who are guaranteed not to get injured. The problem for me is the calling of the game. It puts a lot of stress on me. The way offenses are moving the ball and the rules of the game, that puts enough on a signal caller, now when you get injuries during the game at key positions – like the secondary – it's been going on for four years.
"We had a great meeting of the minds that we have to get bigger and faster in the back end, so we bring in 
On the continued strong play of DT
"He really is playing great. I take the tape and actually grade the tape and put all my statements on the tape so the players can read it and I marvel at some of the plays he's making. It doesn't surprise me because he's prepared since the end of last season. He has made some rushes that are just dynamic."
On safety
"What you miss is his quickness.
"We have a corner that's never played here before and I called a particular defense that should have knocked the reverse in the dirt. The corner doesn't give the safety a key, meaning he had to engage the wide receiver on his side at the snap of the ball -- we call it jump technique -- attacks the receiver and identifies the play for the safety. Well, he stayed off the receiver and it caused
"On the same play, two of the three linebackers don't read their keys and don't come back to help. They guessed it was another play. Guessing gets you beat."
On how disappointed he was with the third down conversions for the 49ers late in Sunday's game:
"I think they were 1-for-8 or 1-for-9 on third down and then we broke down on the critical drive and couldn't stop them. We're one of the better third-down defenses in the league and that's what was frustrating. I think that and the combination of not reading our keys on the run were the most frustrating part of the game."
On the mood after Sunday's game:
"I thought our head coach after the game, he talked to the players in the locker room after the game, I thought he was magnificent. Best I've ever heard a head coach handle a tough lost. He said it was one of 16, you know. The players need to understand that. After the first week some media outlets were anointing some teams and I heard (Patriots quarterback) Tom Brady on Sirius NFL Radio … he said ‘Let me tell you: it's one day at a time, one week at a time.' Jim, much like Tom Brady, addressed the team like that. ‘Put that one in the bag and let's go after it next week and make the corrections.'"
On rookie linebacker
"One play can speak volumes for a guy's career. That definitively could affect him that way. Watching him warm up, he felt comfortable out there. You could see his demeanor change last week at practice. I was really happy for him on that play.
"I saw a guy named Vencie Glenn hit Bo Jackson clear in the face and the ball flew out and we got it and won the game. I was at San Diego and Bo was with the Raiders and (Glenn) became a really good safety. It was a lack of confidence and after that play there was no question he could play this game and played it well the rest of his career."
On RB
"(When we drafted him) I was a little upset because I think we gave up some draft choices when we went up to get him and I was looking for a corner. He was coached by Ron Zook (at Illinois) and Ron was a secondary coach for me when I was the head coach at Kansas City. Prior to looking at the tape I wanted to call Ron, but didn't get a hold of him. He sent word to me, ‘You got the real deal, Gun.'
"We were looking for a four-minute running back at the time and I looked at the tape and said ‘Four minutes? This guy is a running back.' He's more than a big back. He's a good running back."
