The decision to sign Matt Cassel as a backup quarterback paid off Sunday in a 23-20 victory over the Bears, as the former Patriots and Chiefs quarterback passed for 243 yards after replacing Christian Ponder, who suffered a concussion in the first half.

The Vikings trailed by 10 points midway in the fourth quarter, but thanks to Cassel and the running of Adrian Peterson, who gained 211 yards, the Purple was victorious.

Cassel, who started at times for the Chiefs and the Patriots, was asked how he handles coming in cold.

“I think it’s for me now that I have been doing it for a while, it is about always being accountable to your teammates throughout the course of the week,” he said. “I am a firm believer in practice preparation becomes game reality, and by that I mean that you have to put in the work during the week and when your number is called you should be prepared.”

Despite completing 20 of 33 passes for one touchdown and an interception on a pass that should have been caught for a touchdown, Cassel refused to brag about his performance.

“There are a ton of things I am going to watch on film and say ‘Oh my goodness, I can’t believe I did that or this,’ ” he said. “There is always room for improvement. But I am just excited that I was able to help this team to victory today. The offensive line was outstanding. Adrian Peterson obviously had another 200-yard game for him, the receivers did a great job, so offensively it made it easy for me.”

Cassel was asked if a game like this should make him the starting quarterback.

“I don’t make those decisions,” he said. “To be honest my job is to go out and get prepared each week and whatever the coach asks me to do, put my best foot forward. But at the same time my job is to go out there and be prepared and be accountable to those guys in the locker room.’’

Big move by Peterson

Peterson’s performance made him the third-fastest running back in history to surpass the 10,000-yard milestone.

“It really means a lot,” Peterson said. ‘‘A lot of guys have contributed to it over the years — Matt Birk, Steve Hutchinson, Bryant McKinnie and the guys from this year.”

Peterson also added current center John Sullivan and his fullbacks throughout the year who have contributed with their blocking.

“Just to be in that group, it’s truly a blessing,” Peterson said. “God has blessed me to be surrounded by some great guys to help me get to that goal. I sit here and I am just humbled.’’

Peterson was asked how the Vikings rallied from 10 points down in the fourth quarter.

“I was talking on the sidelines with Sully [Sullivan] and some of the guys and said, ‘Hey we are going to get the opportunities,’ ” Peterson said. “The defense is going to make some plays, and they did. ... We were able to march the ball, creating some drives and ultimately put some points on the board.

“It really came to us not giving up. Guys continuing to have faith, and that is what Coach [Leslie] Frazier harps on.

“You have got to believe. You can’t tuck your tail and run, you can’t give up. No matter how it looks you have to continue to fight. That’s one thing that we have done all year. Our record doesn’t show it, but you guys have heard me say it time and time again: I haven’t seen guys quit. When I look in their eyes there is fight there. Today was a perfect example of that fight that we have inside of us.”

One thing unusual about Peterson is that he doesn’t have the home runs he has had in other seasons.

“It’s so funny because I actually think I could have scored on that play,” Peterson said of his 11-yard run that set up Blair Walsh’s winning kick. “But my mind-set was hold on to the ball and get as many yards as possible.”

Peterson has been fighting a groin problem, but he looked healthy enough against the Bears.

Move by Trestman

For Marc Trestman, a former St. Louis Park resident, it was his first time as head coach of the Bears going against the Vikings in the Metrodome.

The tough loss could hurt the Bears’ chances of winning the division.

Trestman will be second-guessed for his decision to let Robbie Gould try a 47-yard field goal on second-and-7 in overtime. The kick missed wide right, giving the Vikings another chance to win.

Asked what his thought was on kicking on second down, Trestman said: “There were a couple of things. We were definitely in range, and I didn’t want to, at that point in time, risk a penalty that would set us back, something similar that had on the other side, or a fumble or something unique. I felt we were clearly in range, and we could get the game over at that time.’’

Trestman has seen Gould make a number of 50-yard field goals, and his percentage was good enough to try it, but it failed and that cost the Bears the chance to win the game.

Trestman paid tribute to Peterson, who had one of his biggest days of this season.

“We were doing everything we could [to stop him],” he said. “Real tough loss, congratulations to Leslie and their team. They played hard, and we didn’t play well enough to win.’’

Bears surprised

The Bears had won seven of the past eight games against the Vikings.

The home team has won 20 of the past 24 meetings, with Minnesota’s victory at Soldier Field in 2007 and the Bears’ wins at the Metrodome in 2006 and 2011 and TCF Bank Stadium in 2010 as the only road victories in the series since 2002.

Well, none of the experts expected the Vikings to have to go to overtime to beat a Bears team that a week ago lost 42-21 to the Rams. The Bears gained 424 yards on offense that day, but they gave up 404, including 258 yards on the ground.

But this was a different Bears team that invaded the Metrodome for the last time.

Wilf can run

Both Mark and Zygi Wilf were on the sidelines when Walsh kicked the winning field goal.

I got a kick out of watching Zygi take off running toward the players, who were celebrating on the opposite end of the field. That man can move.