SANTA CLARA – The 49ers have not played many big games over the past five seasons. But this is the year that changes.

Coach Kyle Shanahan’s team is the only unbeaten squad remaining in the NFL. They can take a major step toward the franchise's first division title since 2012 with a victory Monday night over the Seattle Seahawks at Levi’s Stadium.

The 49ers can take a three-game lead in the loss column over Seattle and the Los Angeles Rams. But a loss would mean the Seahawks would move just one game behind the 49ers and remain unbeaten in the NFC West with a rematch against the 49ers coming Week 17 in Seattle.

“Our team knows where we’re at, and I don’t have to sit there and explain it to them very much,” Shanahan said on the 49ers Insider Podcast. “We have guys who aren’t just along for the ride. This stuff means a lot to our players, from the first player to the last player.

“We got some football people in our building, and they’re not just here to say they’re football players. They want to win, they want to work at it every week. They know we put in a lot of work to get to this opportunity. But that’s just the start.”

The start of the 2019 season is a dramatic departure from the two seasons since Shanahan and general manager John Lynch have taken over with the 49ers. The 49ers opened 0-9 in 2017, and were 1-7 last year.

But with more victories, there come different issues, Shanahan said.

“We’ve had some real bad records here over the last two years, especially to start out,” Shanahan said. “And when you’re 1-6 or 0-8 or whatever it is, people think that’s the most stressful thing in the world, which it is. It’s pretty miserable.

“But 8-0 is not much different. Eight-and-oh doesn’t mean anything. It means you have an opportunity, but it gets harder and harder.”

The 49ers are in the midst of a five-year playoff drought. After the team’s best start since 1990, there are plenty of expectations for the 49ers that did not exist in the past few seasons.

“There’s more pressure because you don’t want to mess this up,” Shanahan said. “We’ve gotten a chance to be where we’re at, and now we got to make sure we get in those playoffs. Every game matters.”

Even beyond an NFC West title, the 49ers have their sights set on winning enough games to earn a first-round bye in the playoffs. The 49ers also can strive for home-field advantage throughout the playoffs.

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“We have to get better each week as we go if we want to accomplish what we want to accomplish,” Shanahan said. “I do know from my history of being in this league, at the end of the year, only one team is happy. And I’ve never been happy at the end of the year.

“Eight-and-oh is nice. We’re enjoying it, so far. But this is just the start. We have a lot ahead of us, and we’re only going to be happy if it ends one way."