Lewis was sanctioned by Cricket Australia (CA) for a Level Two Offence under the CA Code of Behaviour. Lewis pleaded guilty to the charge of breaching Article 2.2.9 of CA's Code of Behaviour - changing the condition of the ball in breach of law 42.3 of the Laws of Cricket.
The former Australian one-day paceman was later charged by match referee Steve Bernard and accepted a fine equal to 50 per cent of a player's match fee (a fine of $2,266).
Cricket Victoria issued a statement on Tuesday morning, saying Lewis' actions wouldn't be tolerated.
"Cricket Victoria does not condone any action to gain an unfair advantage in any form, we're committed to playing fair cricket in the spirit of the game," Cricket Victoria chief executive Tony Dodemaide said.
"Myself and Cricket Victoria chairman Russell Thomas immediately spoke to Mick and he has apologised unreservedly and understands that this reflects unfairly on the Bushrangers and all of Victorian cricket.
"Mick pleaded guilty to Cricket Australia's code of behaviour breach and has also accepted a severe reprimand, imposed upon him as a Cricket Victoria employee, and assured us that actions such as this will not happen again.
"Mick also went personally to South Australian coach Jamie Siddons and apologised after the day's play ... We believe that Mick will learn a valuable lesson from this and understands this type of behaviour will not be tolerated."
Lewis' action surprised as the defending champion had outplayed South Australia over the first three days of the 2015-16 decider.
Victoria is on track to be the first team since 2004-05 to win a Sheffield Shield final away. Peter Handscomb and Travis Dean posted glorious first innings tons in Victoria' first innings 399.
As this was Lewis' first offence under the Cricket Australia Code of Behaviour within the last 18 months and he accepted the charge, no hearing was required.
CA Head of Operations Sean Cary said: "Ball tampering is a very serious offence and simply won't be tolerated at any level of the game.
"Match Referee Steve Bernard addressed the matter as soon as it was brought to his attention, spoke at length to Mick Lewis about it and has handed down the subsequent penalty.
"We acknowledge that he has apologised to the South Australian team and the match officials and hope the matter deters others from doing anything like this in the future."
-News.com.au