In the end the Saints only contested one of the four charges laid against Baker for his clashes with Geelong's Steve Johnson on Friday night.
The club challenged the misconduct offence for unnecessary contact with an injured player but failed to overturn the verdict, adding two matches to the seven he received for early guilty pleas to three striking charges.
The Saints have not ruled out taking the matter further and will consult with the club's board on Wednesday.
"The St Kilda Football Club and Steven Baker are extremely disappointed with the extent of the penalties that have been imposed upon them," St Kilda CEO Michael Nettlefold said.
"On any measure, for what has been confirmed as four low impact incidents by the tribunal, it is a most significant and extreme impost on Steven and the club.
"In terms of any further action the club may take, the St Kilda board will now consider its position."
The hearing started nearly 20 minutes late as the Saints reconsidered their earlier decision to contest the first of three striking charges after reviewing the footage of the incident on the AFL's high definition television.
The early guilty plea for that charge, which occurred before the first siren, saw another two games added to the five Baker had already accepted before the hearing.
St Kilda player advocate Tony Nolan SC attempted to have Baker's misconduct charge dismissed by pointing out the difference between injury and discomfort, and by claiming there was no evidence Johnson had a broken hand.
Once tribunal chairman David Jones directed the case to proceed, the Saints and Nolan argued that Baker did not know Johnson was hurt as no trainer ever came onto the ground to attend to him.
However, the jury - consisting of Wayne Henwood, Michael Sexton and Wayne Schimmelbusch - found in favour of legal counsel Andrew Finney SC's claims Baker was well aware of Johnson's injury and intended to connect with it six minutes into the first quarter.
Finney said there was footage that showed Johnson favouring his right hand before the incident, and questioned why Baker would specifically target a "hardly typical" area of the body without reason.
He also said there was "nothing brave about targeting injuries" and said Baker's actions were not in the spirit of the game.
After the verdict, the Saints tried again to reduce Baker's suspension by pleading "exceptional and compelling circumstances" led to the escalation of his sanction.
Nolan asked the tribunal to consider a monetary fine in place of a suspension when taking into account the number of games he had already lost with the previous three charges.
The jury said the question of the three earlier penalties was not a matter for the tribunal to take into consideration.
Baker will not play another home and away game this season, but will be eligible to play from the first week of this year's finals series.
Baker's sanction sits among some of the most severe in the game's history.
Essendon’s Phil Carman was suspended for 16 matches for headbutting boundary umpire Graham Carbery in 1980. St Kilda’s Robert Muir was suspended for 12 weeks in 1984 for two striking and one head-butting offence, while Essendon’s Terry Daniher was given a total of 11 for a pair of striking charges in the 1990 grand final.
Brisbane Lion Alastair Lynch went out swinging in his final game when he drew two striking and four attempted striking charges in the 2004 grand final. He received a total of 10 weeks.
After the infamous 2000 West Coast-Fremantle derby melee, Dale Kickett was found guilty of three striking charges and handed a nine-week ban for collecting Phillip Read twice and Andrew Embley once.
Baker himself has a colourful tribunal history, having been suspended for a total of 17 games - 11 since the inception of the match review panel in 2005.
His biggest previous penalty from a single match came in 2007 when he was outed for seven games for rough conduct against Fremantle's Jeff Farmer.
It remains the biggest sanction handed down by the match review panel behind Dean Solomon's eight-match ban for fracturing Geelong captain Cameron Ling's cheekbone in 2008, and equal with Barry Hall's sanction for his infamous strike against Brent Staker in the same year.
