SANTA CLARA, California. – For most teams in the NFL, especially this year's version of the Cowboys, it takes four really good quarters of football to win a game.

However, it only takes one truly terrible quarter to lose a game.

The Cowboys found that out the hard way here Sunday night when they were beaten by the 49ers, who completely dominated them in the third quarter.

Sure, the Cowboys won the other three quarters by a combined score of 17-9. But it doesn't matter if you come out of halftime up 21-0.

Seriously? Twenty-one points to zero in the third quarter?

Well, that's what ultimately doomed the Cowboys, but they couldn't help themselves either early in the first quarter or at the very end. The old saying “Now it’s how you start, but how you finish” doesn’t always apply to football.

In fact, in today's NFL, where games are designed to go to the finish, it usually comes down to how you start… and how you finish.

And the Cowboys didn't do either well enough to win this game.

Wow, if this game didn't look a lot like the Ravens' loss a few weeks ago. For me it was pretty much the same game. The 49ers took control, especially in the ground game, and looked like they were going to blow away the Cowboys. But then, in a bit of a “too little, too late” category, the Cowboys rally and come pretty close to getting back in the game – only to fall short in the end.

And that's exactly what happened again. Yes, the 49ers hit a bit of a lull on offense and stopped scoring after a great third quarter. And the defense gave up some plays to CeeDee Lamb as the Cowboys struggled to get back in the game.

But at the very end, when the 49ers defense had to be stopped, the Cowboys didn't even get a yard. And then the San Francisco offense took over, got a crucial first down and the game was over.

Add that to the Cowboys' teething troubles and you're looking at a 30-24 loss to the 49ers, who have dominated this rivalry in recent years.

And honestly, I really don't know why I'm surprised, but I was. I seriously thought the Cowboys were going to show us something completely different.

While all of my colleagues around me picked the 49ers to win based on recent history, I also made my choice based on history. Something told me the Cowboys would be a different team after the game. That's how it was among Mike McCarthy-coached teams. I took that combined with the 49ers' recent injuries and thought they might be able to pull out a win.

Turns out the bye week really didn't help the Cowboys.

Sure, it might have started out as if everything was different, and there was that excitement in the fourth quarter, but in the end – at the very end – the 49ers did whatever they wanted, no matter who was in the lineup or not.

And that is a credit to the 49ers and their coaching staff for what has been built here. Yes, they're not the same offense without Brandon Aiyuk and Christian McCaffrey, just like the Cowboys aren't the same without Micah Parsons, DeMarcus Lawrence and DaRon Bland, but San Francisco still finds a way to be functional. And they were better against the Cowboys defense. After a slow start, the 49ers figured out how to beat the Cowboys in the third quarter and that made the difference in the game.

And honestly: who is surprised?

I came across this statistic two weeks ago and I've probably overused it, but until the Cowboys fix it, I'm going to keep saying it because it's once again rearing its very ugly head: The Cowboys were terrible at the start – early in the game , at the start of the second half. And it's both sides of the ball.

After seven games, this is more than just a trend, it's a pretty big problem.

The Cowboys have not scored a touchdown at the start of a game, but still continue to take the ball if they win the toss. Once again, the Cowboys immediately hit a punt, which was rather depressing given the two-week layoff. One would think they had something better planned than just a first down and a punt.

But don't get too upset about the Cowboys taking the ball early in the game. They don't do anything with the ball at the start of the third quarter either.

On offense, the Cowboys now had 14 possessions at the start of a game or a half and were only able to produce three field goals – none of which came on Sunday evening.

Unfortunately, the defense was even worse at the start of games and halves. The teams have scored 13 goals out of the 14 possession games they have played this year. Seriously? This means that the opponent scores 92 percent of the time on the first drive of a half.

That's absurd. And I'm sorry, it depends on the preparation – both for the coaches and for the players.

We've heard players, especially Dak Prescott, say too many times this year that training needs to be better. We heard Jourdan Lewis talk about the players not being “detailed” enough in their preparation work, both in practice and in the film room.

And that's the part that shows itself the most when you start a game and when you come out of the locker room in the third quarter. There doesn't seem to be any adjustments at all and the team just keeps getting better.

Add up all the opening attacks, both offensive and defensive, and the score is 71-15.

Yes, the Cowboys are outscored 71-15 on the first drives of each half this year. To me, this is the official result of an underlining problem: the Cowboys are being outsmarted and outplayed, and it all results in them being outgunned.

Okay, so the Cowboys came together late to turn what looked like a blowout into a one-score game with a chance to win, but they couldn't.

They struggled at the beginning and couldn't make it in the end. If you do that often enough, it doesn't really matter what happens in between.