SANTA CLARA, Calif. – How dominant and suffocating was the Seattle Seahawks defense against the San Francisco 49ers on Thursday night?

Niners quarterback Colin Kaepernick, who was picked off twice by Richard Sherman, fired blanks when it came to throwing downfield in the 19-3 defeat.

Consider: per ESPN Stats & Information, Kapernick was just 4-of-15 passing when throwing the ball deeper than five yards downfield, for 37 yards and those two Sherman interceptions. As such, his eight off-target throws at that distance are tied for the most in a game in his career.

“We keep working,” Kaepernick said after the game. “Worrying about it, complaining about it, being frustrated with it, isn’t going to help us get better. We keep working. That’s the only way it’s going to get right.”

When it comes to passing deeper than five yards, Kaepernick completed 9.8 such passes through the Niners’ first 11 games and completed 54.5 percent of those throws, with 167.7 of his passing yards per game coming on those passes, with 11 TDs with six interceptions.

The Seahawks limited Kaepernick to a career-low 26.7 completion percentage on such passes.

And the deeper he threw it on Thanksgiving, the worse the result. According to Pro Football Focus, Kaepernick was 0-of-10 on throws of at least 10 yards. And yes, both picks came on such throws.

“We had zero big plays,” said left tackle Joe Staley, who had a costly penalty to stall a 49ers drive. “Zero.”

Said receiver Michael Crabtree, when asked if he was surprised the Niners could not get anything going offensively: “Am I surprised? We got 70 yards [of offense in the first half]. It’s not supposed to happen like that. We’ve got to do better. It is what it is.”

There are only four games remaining and Kaepernick said the 49ers have to win out to have a shot at returning to the playoffs.

“Everything we need is in the building,” Kaepernick said. “We have great players across our offense. We have to go out and play like it.”