SAN FRANCISCO - Just two months ago, the San Francisco 49ers grabbed control of the NFC West from the Arizona Cardinals behind Alex Smith's near perfect performance on a Monday night in the desert.

Oh, how much has changed since.

The slow and steady Smith has been replaced by Colin Kaepernick, a high-risk, high-reward quarterback who coach Jim Harbaugh is counting on to lead the suddenly fragile 49ers (10-4-1) deep into the playoffs. The Cardinals (5-10) are on their fourth starting quarterback in Brian Hoyer and have lost 10 of 11 games to put coach Ken Whisenhunt's job in jeopardy.

One team is headed to the postseason, the other for a head start on the NFL draft. The only question left is where each will be seeded for their final destinations.

San Francisco can clinch its second straight division title and keep its shot at a first-round bye alive in today's regular-season finale against Arizona at Candlestick Park. The once promising Cardinals are 60 minutes away beginning another offseason of upheaval.

"Sometimes in a game like this, anything goes," Harbaugh said. "Their mindset will be to win the game. So you have to be ready. You have to be alert for just about anything."

Hoyer is making his first NFL start, less than three weeks after the Cardinals claimed him off waivers from Pittsburgh.

Hoyer was out of a job for most of the year and then relieved Ryan Lindley in Arizona's 28-13 loss to Chicago last week. He has appeared in 14 NFL games, including 13 with the Patriots.

"It's a crazy business, but to me it's the best job in the world," Hoyer said.

Arizona started the season with four straight wins before suffering a nine-game losing streak.

The matchup

• What: Cardinals at 49ers, 2:25 p.m. on Channel 11

• The line: 49ers by 16 1/2

• Record vs. spread: Arizona 6-8-1; San Francisco 9-6

• Series: 49ers lead 25-17

• Notable: 49ers can clinch NFC West for second straight season with win or Seattle loss against St. Louis. ... Arizona wide receiver Larry Fitzgerald has just 69 receptions for 785 yards.