Today's game between the 49ers and Lions is the marquee game in the National Football League.

It felt strange writing that sentence. For a long time, the Niners and Lions have been among the bad teams in the league — especially the Lions. Their last winning season was in 2000 when they won nine games. In 2008, in case you forgot, they won exactly no games — totally whiffed on their 16-game schedule.

The Niners, as you are painfully aware, haven't exactly torn up the league. Their last winning season was 2002 with a 10-6 record. Since then it's been Dennis Erickson and Terry Donahue and Mike Nolan and Mike Singletary and that never-ending Alex Smith debate.

The 49ers and Lions each had 6-10 records last season and gave no indication to sane people they would be excellent football teams in 2011. But their combined record is a gaudy 9-1 and they are playing today's marquee game as opposed to, say, Dallas at New England or any other matchup you can name.

Two perspectives exist on the bigness of this big game for the 49ers — players and fans. Let's first look at the players' perspective. Here is offensive lineman Adam Snyder:

"I don't know if it's the biggest game we've ever played in, but it's a big game for this season. We need to approach it like that. If we get too blown up on it — &‘This is the biggest game of our career' — guys start playing tight and that's not what we want to do. Right now, we're just focused on what we have to do as an offense."

In what sense is this a big game?

"There are two good teams colliding. They're 5-0 and undefeated and they're on a little bit of a hot streak, and we're playing some good football, too. Two good teams coming together is always going to be a good matchup. I try not to read into the hype — &‘This is the biggest game we've ever played' — but, yeah, if you look at it, it is a big game."

Snyder has a rational, cautious, professional approach to the game. Alex Smith does, too. But his words, as always, resonate and have a subtext. Here is Smith:

"They all seem like every week they're big. When we were playing the Eagles, that was the biggest test, and now this is. This is a great test for us."

I pointed out he's never played a game of this enormity as a 49er.

"We're not sitting here dwelling on the past. It's another football game. We're playing a team at their place. They're 5-0. They're playing really good football. We're focused on what we need to do, not looking at the teams' combined records and the meaning behind it."

I persisted. Smith invites you to persist. I said this is the first time the 49ers have mattered in a long time, and the first time they've played a game that matters.

"When you're in the locker room and when you're putting on the shoulder pads, they all matter," Smith said. "When you're stepping out there, we've got the Niners on the front of our jersey. We've got our names on the back. We're playing for each other and we're playing for pride. They're all meaningful.

"In years past, it's Week 14 and we're still in the hunt. Like last year, 7-9 won the division. You're still in it late in the season. Every time you strap on that helmet, every time you put on the shoulder pads and you walk into those lines on that field, it's enough as it is. You're playing for your pride. You're playing for your job. All of a sudden the two teams' records — you're still just playing a football game and trying to win."

As you read that eloquent response, you felt Smith's deep-down pride in himself and the enterprise he's chosen to pursue. But earlier I wrote there is a second perspective to this game, the fan's perspective. To a fan — a fan who is honest about this — today's game will define the 49ers in some way, at least as a winner or loser of this big game, this marquee game. And almost certainly it will define a lot more.

We will know if the 49ers offensive line can deliver against that scary Detroit defensive front seven. We will know if the 49ers, who surely want to run, will be able to run — I think they will be able to run against the Lions' hyper defensive front. We will know if Smith can retain his poise in the chaos on the field or if he reverts to you know what. We will learn if the 49ers defense can confuse Matthew Stafford — a distinct possibility — and if they can limit the receptions of the Lions' marvelous receiver Calvin Johnson.

There is a whole story out there waiting to be written. Lots of people say the Niners can't beat the Lions. They said that about the Buccaneers, too.

For more on the world of sports in general and the Bay Area in particular, go to the Cohn Zohn at cohn.blogs.pressdemocrat.com. You can reach Staff Columnist Lowell Cohn at lowell.cohn@pressdemocrat.com.