Let's face it: This Vikings defense is not the same without Kevin Williams, who was suspended for Sunday's 24-20 loss to Tampa Bay, as well as departed starters Pat Williams, Ray Edwards and Ben Leber.

Still, it is hard to figure out how the Vikings offense, which looked so impressive in the first half at San Diego a week ago, then did nothing in the second half. The offense duplicated that Week 1 performance Sunday on its home turf, managing only three points after halftime as the Buccaneers came back to win.

It is difficult to understand the difference in stats between the first half and the second. The Buccaneers had only 62 yards of offense in the first half compared to 284 by the Vikings. In the second half, the Bucs had 273 yards to the Vikings' 114.

Adrian Peterson had 15 carries for 83 yards in the first half but gained only 37 yards on 10 carries in the second.

Then you have Toby Gerhart, who carried twice for 32 yards in the first half and also took a screen pass 42 yards on third-and-long. In the second half, Gerhart never got a chance to touch the ball.

People can blame both the offensive and defensive units for their failures to play competent football for a full 60 minutes in both games. Sure, you have to say that the Vikings defense has not been able to stop the opposing defense from marching up and down the field, but at the same time, when the offense gets the ball back, it has to give the defense a rest by sustaining a long drive or two.

One big improvement in the Vikings offense over last week was the passing performance of quarterback Donovan McNabb, who completed 18 of 30 passes for 228 yards -- but 153 of those yards came in the first half. Still, it was a big gain from his 39 passing yards against the Chargers.

Is the answer that both the Chargers and Buccaneers have done the better job with second-half adjustments? Or are the Vikings on their way to another losing season like last year's 6-10 campaign?

We might get that answer next week when a hot Detroit Lions team comes to town after destroying the Kansas City Chiefs on Sunday. The Lions stand at 2-0, including a Week 1 road victory against the same Tampa Bay team that came back to beat the Vikings on Sunday.

Allen in disbelief

Vikings star defensive end Jared Allen, who got called for an unfortunate 15-yard penalty for roughing the quarterback on the Buccaneers' first fourth-quarter touchdown, said of Sunday's terrible second half: "I'm in disbelief. I can't believe what just actually happened."

"It's all in this locker room," he said. "I'll be honest. I'm not trying to take anything away from Tampa Bay, excuses are worthless. They started executing, but I've got to be honest with you -- obviously I congratulate them for taking advantage of the opportunity, but we, as a defense, have to be better than that, and we have to own this one and we have to go out there and win a game for us. We flat out blew a 17-point lead, and that's unacceptable."

About his personal foul, which was immediately followed by a 25-yard touchdown pass from Josh Freeman to Arrelious Benn, Allen said: "It was legitimate. I was just trying to make a play. I have to eat that one."

Asked if the Vikings miss Kevin Williams, one of the best defensive tackles, in the game, Allen said: "You know, we miss everybody, but I wouldn't say one bad thing about the guys we got. I think everybody is playing their butts off. Erin [Henderson] is playing well, Robi [Brian Robison] is playing well, Letroy [Guion], and even the rookie [Christian] Ballard is doing all right for us. We obviously miss Kevin tremendously, and big Pat, they're personality guys. But that's what this is, major league business. People come, people go, we have to step up and play like we did in the first half of these first two games for 60 minutes."

The Vikings did a great job of rushing Freeman early on, but the Tampa Bay offensive line did a great job of protection in the second half.

"I thought we did some good things up front getting to the quarterback," Allen said. "But they started checking down. I don't know, we have to watch film and we have to figure it out."

Mistakes hurt

Pro Bowl guard Steve Hutchinson said the Vikings didn't help their cause with their many mistakes. The Vikings were penalized eight times for 65 yards.

"I think we killed ourselves with penalties and missed opportunities. Just didn't finish the game," Hutchinson said. "We've got to correct the mistakes."

Needed first win

Gophers coach Jerry Kill was thrilled for his players after his team beat Miami (Ohio) for its first victory Saturday.

"They've gone through a lot of adversity over the last two weeks," Kill said. "... It was good for them to feel good. Won a close game and I think they tried to play hard and tried to do the things that our coaching staff asked them to do."

One of the Gophers' biggest plays came on special teams, when running back Duane Bennett blocked a punt, recovered it and returned it for a touchdown. "We told them we were probably going to have to make a special teams play, we were going to have to block a punt, we're going to have to get a kickoff return, we're going to have to do something special to win," Kill said. "And we blocked a punt."

Revisiting his decision to go for it on fourth-and-9 at the Miami 34-yard line, Kill said: "We're still learning in the punting and kicking game, as you know. I didn't know if we could set it down. ... Hindsight is 50/50, and if [Miami wins], I'm sitting here, and they say, 'Boy, that was not very smart.' And I understand that."

Gray is improving

Kill was impressed with junior quarterback MarQueis Gray's decision-making with the Gophers offense. He ran 21 times for 171 of the team's 236 rushing yards.

"But I think that the thing about MarQueis, again, he's played three games at quarterback and it's been four years. He'll get better," Kill said. "A couple times, the ball slipped out of his hand. He's got big hands, but he's sweating so much. Sometimes that ball, he squeezes it so hard, it squirts out of his hands. He's getting better and you can tell he's getting more confident."

If the Gophers are going to win some games, one thing they are going to have to do is convert on third down a lot better than their 3-for-13 showing Saturday.

Sid Hartman can be heard weekdays on WCCO AM-830 at 6:40, 7:40 and 8:40 a.m. and on Sundays at 9:30 a.m. • shartman@startribune.com