SANTA CLARA – Defensive coordinator Vic Fangio said Thursday that 49ers safety Dashon Goldson's big hit on New England Patriots tight end Aaron Hernandez on Sunday was perfectly legal.

The NFL ruled otherwise.

Goldson learned Thursday he's being fined $21,000 for the third-quarter play, which drew a 15-yard penalty. Goldson said he will appeal.

Goldson has been penalized for more yards – 102 – than any other 49ers player and ranks seventh in the NFL. All but one of his penalties have been 15-yard personal fouls.

Still, Goldson said he hasn't been fined for the majority of those hits. He was fined $7,875 for taunting Seattle running back Marshawn Lynch in Week 7, and he hit a sliding Sam Bradford late in a game against St. Louis, drawing another $7,875 fine.

Goldson, however, vowed that the fines won't change his style of play.

"I don't have time to sit there in the time span I have as a football player when I'm on the football field to decide what's clean and what's a not-so-clean hit," he said. "I'm not a dirty player. And that's just that."

Fangio said the 49ers coach their players to hit legally and he believes Goldson did so because he wrapped up Hernandez as he made the tackle and struck him in the chest.

"I think what's happened is if it looks bad, the league has told the officials to err on the side of caution," Fangio said. " … A lot of times if they don't see it all and it's a bang-bang play – it's a hard play for them to see sometimes – they're going to err on the side of safety and throw the flag."

Goldson has a locker full of manila envelopes from the league.

Many are uniform violations, including those regarding the length of Goldson's socks. He said those infractions are $5,000 and $10,000 each and that he's probably been fined $70,000 this season.

Cyber threat – For the second time this year, a 49ers player has discovered that having a direct link to fans via social media has drawbacks.

Kicker David Akers, who has struggled in recent games, re-tweeted a threat from a follower that said Akers would have his "entire life ended" if he missed another kick. Akers appears to have disabled his Twitter account shortly thereafter.

Akers, a 15-year veteran, is 25 of 35 on field goals after setting an NFL record for total field goals made (44) last season. Asked Monday if he is considering a change at kicker, coach Jim Harbaugh said, "No, not at this time."

Wide receiver and return man Kyle Williams received death threats via Twitter after two muffed punts in the NFC Championship game in January.

Smith absent – Justin Smith (elbow) missed his second consecutive practice, raising the prospect that Ricky Jean Francois will start at right defensive end Sunday in Seattle. Smith has started the most consecutive games – 185 – of any defensive lineman in the league.

© Copyright The Sacramento Bee. All rights reserved.

• Read more articles by Matthew Barrows

Order Reprint