The Arizona Cardinals were playing with a little more pride and conviction on Sunday than most San Francisco 49ers' fans were probably comfortable with. The Cardinals hung around in the first half, before the Niners' momentum, which started rolling around mid-season, barreled through Arizona for a 38-13 victory. There would be no breaking the 49ers' winning streak, which culminated yesterday in 10 straight Ws — plus six-straight wins for Brock Purdy — for a 13-4 record on the year.

The question on every 49ers fan's mind now is: How deep can this team go into the playoffs?

"When you're on a roll, you feel [in] the groove," said Brock Purdy after Sunday's win. "I think a lot of us feel like we still haven’t played to our full potential yet."

Despite yesterday's lopsided score, Brock Purdy was flushed out of the pocket a few times, and took two sacks from J.J. Watt — who was playing in his last game — in the 49ers' victory. (Photo by Ezra Shaw/Getty Images)

It took a moment for the permutations to finally settle yesterday and spit out next week's matchups. The Detroit Lions, who had been eliminated before their game against the Green Bay Packers began last night, were also playing with a lot more pride and conviction than might have been expected.

The Lions ultimately sent Aaron Rogers and the Packers packing, opening the door instead for the 9-8 Seattle Seahawks to visit Levi's Stadium on Saturday, the first playoff game of this year's postseason.

San Francisco beat out the Minnesota Vikings on a tiebreaker for the second seed, "assuring the 49ers won’t have to go on the road before the NFC title game," the AP reported.  (There had been some jocular musings that the 49ers should have tanked yesterday's game to secure the No.3 seed and avoid Rogers and the Packers, who probably have some score-settling to do after last year's crushing loss to the Niners in the divisional round.)

Still, with one of the best records in the league, it's kind of a bummer that the 49ers have to play in the wild-card round. Meanwhile, the 8-9 Tampa Bay Buccaneers will host the 12-5 Dallas Cowboys next Monday night.

George Kittle had another two touchdowns yesterday, including this toe-dragger late in the first half of the game. (Photo by Thearon W. Henderson/Getty Images)

Thank goodness all of the numbers have finally been crunched, and we can get on to the real business of worrying about Seattle.

Should we worry? Statistically, no. On paper — and by every other objective measure — the Niners are by far the better team; they're favored by 10 points next week. That's what worries me.

The NFL postseason is unforgiving with very little margin for error. (Just ask Rogers and the Packers.) But the Niners have been playing error-free, playoff-caliber football for several weeks now, finishing the season with the best-ranked defense in the league and the fifth-best offense. There are times when I have to remind myself that Brock Purdy hasn't been the Niners' QB for three-plus years, and that he doesn't already have a few seasons of playoff experience under his gold belt.  

I have to fight the temptation to continually expound on the unlikely ascendence of Brock Purdy, or to be continually amazed at one of sport's great Cinderella stories. Now that the regular season is over, none of that matters. Purdy is no longer the heroic third-stringer that rose from "irrelevance" in a dark moment to quarterback a very good team who was, in all likelihood, already destined for the playoffs. Now, Purdy is simply the Niners' QB. He's The Guy. He's gotten his reps in. The goal is clear and simple: Win the next four games.

(Though it's still too early to say this, and even though I don't believe in jinxes, I'm kind of worried that I'll jinx it [Please don't read this if you feel like I'm tempting fate]: No rookie QB has ever won the Super Bowl. Yes, Kurt Warner and Tom Brady won it all in their first year as starters, with Brady coming in during Week 2. It's not clear to me at what point, or in how many games, someone goes from "rookie" to "starter.")

In a season of crushing, season-ending injuries for the 49ers, Deebo Samuel made his return yesterday. Samuel had just two receptions for 20 yards, but the Niners' arsenal of offensive weapons is looking healthy and deep again. (Photo by Thearon W. Henderson/Getty Images)

The Niners swept Seattle this season, beating the Hawks 27-7 in Week 2 at Levi's, when Trey Lance went out with a broken ankle and Jimmy Garoppolo unexpectedly got another shot at QB. The 49ers beat the Seahawks again less than a month ago, this time 21-13 in Seattle, in Brock Purdy's first-ever road game, and second-ever career start. Next week's playoff game will mark the 49ers' second postseason meeting with Seattle; the Seahawks beat the 49ers, 23-17, in the NFC Championship Game in January 2014, the San Francisco Chronicle reported.

The stage is set, but hopefully the Seattle Seahawks are nothing more than a quick Act 1 on the path to something much more dramatic.

The 49ers will take on the Seattle Seahawks at 1:30 p.m.

Top Image: Photo by Thearon W. Henderson/Getty Images