Santa Clara, Calif. – The Vikings hoped Kirk Cousins would transform them.

Instead, he has become them.

He is good enough to inspire hope, and flawed enough to destroy it. He quarterbacks perhaps the most accomplished franchise to never win a Super Bowl and if he is not a roadblock, neither does he appear to be an elevator.

After the Vikings' 27-10 loss to the San Francisco 49ers at Levi Stadium on Saturday, Cousins owns a 1-1 playoff record with the Vikings and is 1-2 in the playoffs overall for a franchise that hasn't won multiple playoff games in a season since 1987.

He has won 57% of his starts for the Vikings. The Vikings have won 55 % of their games in franchise history. For what ails his team, Cousins has been more placebo than penicillin.

So congratulations to everyone with an opinion about Cousins. He spent this season proving you right.

If you believed that he was wrongly vilified as an uninspiring leader prone to self-immolation in big games, well, Cousins will always have New Orleans, where he produced a game-winning drive in overtime in a stadium that couldn't have been louder had Metallica been playing at midfield.

If you believed that Cousins could look anxious on any given play or day, you can wince at the memories of his fluctuations at Green Bay and Chicago early in the season, or against Green Bay and San Francisco late.

Saturday, Cousins led an offense that managed just four first downs while the game was in doubt, through the middle of the fourth quarter.

Was this all Cousins' fault? No. The 49ers were physically dominant. Cousins felt pressure much of the game and his lone interception was the fault of receiver Adam Theilen.

If Cousins doesn't deserve primary blame, neither does he deserve absolution. He made one impact play, a 41-yard touchdown pass to Stefon Diggs in the first quarter, and rarely attacked downfield afterward, even when he had time.

Another pass to Diggs proved more emblematic of this game a career that remains prolific yet uninspiring.

At the end of the first half, the Vikings faced third-and-9 at the 49ers' 17. Diggs ran a down-and-out. Cousins, with time to throw, and fired a low pass that beat Diggs to the sideline. Cousins reacted by holding his head, and the Vikings settled for a field goal.

"When I was throwing it, I thought we had it,'' Cousins said. "The corner was off and I think I just pulled him too far to the sideline and just didn't connect on it.''

Some throws matter more than others. And some throws leave receivers, open downfield, wondering why they didn't get the ball. "There was one to Irv [Smith] that I would have liked to have taken,'' Cousins said.

Cousins completed 21 of 29 passes, which gives you a reasonable passer rating and vacation time in January.

He has one year remaining on his three-year contract for a franchise that hasn't yet tried to find or develop a successor. "It's just not my focus right now,'' he said. "My focus is on this game, the playoffs. I certainly love it here and love being a Viking.''

Soon, the Vikings will choose to offer Cousins a contract extension, or to let him play 2020 as a lame duck quarterback. He is 19-14, including 1-1 in the playoffs, as the Vikings' starter. In the two seasons before he arrived, the Vikings went 22-12, including 1-1 in the playoffs.

Do they invest heavily in a quarterback who this season ranked 13th in ESPN's QBR? Probably. Can they hope to do better with a free agent or draftee? Probably not.

A contract extension would be sensible for both parties, but being sensible could leave the Vikings banging their heads on their patented glass ceiling for years.

They're a pretty good team. Cousins is a pretty good quarterback. That combination can be comforting, but it's not likely to bring the franchise its first Super Bowl victory.

Jim Souhan's podcast can be heard at TalkNorth.com. On Twitter: @SouhanStrib. • jsouhan@startribune.com