GLENDALE, Ariz. -– With all the questions whether the 49ers still have enough good players to be competitive on a weekly basis, quarterback Colin Kaepernick said none of that mattered on Sunday.

“We have good players,” Kaepernick said following the 49ers’ 47-7 loss to the Arizona Cardinals. “We just have to perform. Today was 100-percent my fault. There’s nothing anyone in that locker room could’ve done to change that game today the way I played.”

Kaepernick took the blame. So did first-year head coach Jim Tomsula, who stated, “It starts and ends with me.”

Kaepernick had the worst game of his career. He completed just 9 of 19 passes for 67 yards with no touchdowns and a career-worst four interceptions. His first two interceptions were returned for touchdowns. His passer rating was 16.7.

Tomsula said there was no thought given at any point in the game to benching Kaepernick and going with backup quarterback Blaine Gabbert. Tomsula said he wanted Kaepernick to get some success going and work his way out of the funk. It never happened.

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“I think the world of that guy,” Tomsula said of Kaepernick.

Kaepernick said it’s a good feeling to know his coach is going to stand behind him in bad times.

“As a quarterback, it’s great to know that your coach supports you and is going to allow you that opportunity,” Kaepernick said.

 

After Kaepernick threw his second interception, the 49ers’ next 13 plays were runs –- a streak that included two scrambles. Tomsula said he sent the directive to offensive coordinator Geep Chryst to run the ball during that stretch of the game.

“Let’s grab ahold of this and get things calmed down,” Tomsula said was his reasoning by sticking with the running game.

It was the first four-interception performance of Kaepernick’s career after twice having games in which he threw three interceptions.

“(It’s) very hard for me to deal with,” Kaepernick said. “Very hard to see myself go out and play like that and hurt this team the way I did. I nullified all the efforts of every other player on that field today. That’s something I have to fix. I have to be better for this team moving forward.”

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The 49ers were never in the game after forcing a punt on the Cardinals' first offensive possession.

On a third-and-11 play from the 49ers’ 12-yard line, Cardinals cornerback Justin Bethel broke in front of tight end Vernon Davis to intercept Colin Kaepernick's first pass of the game. He took it 21 yards for a touchdown.

Just two minutes later, Kaepernick threw to Anquan Boldin. This time, safety Tyrann Mathieu ducked underneath Boldin to intercept the pass. He returned it 32 yards for a touchdown, giving Arizona a 14-0 lead after less than six minutes of play.

“The first pass I just have to put it further outside and allow Vernon to make that play,” Kaepernick said. “The second one, got a little pressure and rolled right, thought I could fit that one into Anquan and got undercut. Both of those are my fault, my mistakes that hurt this team.

“You go back to work. There’s nothing you can do as far as dwelling on this game. It’s not going to help you moving forward and it’s not going to help you win the next game. You look at the film and you learn from it. And we have to be ready for Green Bay.”