Savea will miss the home match against the Blues this Saturday.
He was issued a yellow card after a scuffle against the Melbourne Rebels on Friday. As he left the field, Savea made the gesture towards Rebels halfback Ryan Louwrens.
The SANZAAR judicial panel decided the throat-cutting gesture was close to warranting a red card, and agreed it was a yellow card offence. Because two yellow cards in the same match become an automatic red card and sending off, the panel reconvened for a new hearing.
The second hearing decided on Tuesday that Savea should be suspended for a week.
Savea said he apologised to Louwrens and also had to answer to his father Masena, who called him immediately after the match.
"It's just the heat of the moment, it's a warrior game but I've got to lead by example, being skip, so I got that wrong," Savea said.
"There was a bit of banter going on and it got the better of me.
"I got off the field and my old man called me and kind of growled me off so that's a lesson learnt.
"I understand the role I play with the kids watching the games ... it doesn't excuse what I did but we make mistakes and hopefully I grow and learn from it."
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