Grant immediately launched an appeal after the prison sentence was handed down and will seek release on bail.
The 41-year-old faced Moorabbin Magistrates Court and admitted assaulting the woman at his house in Highett, at a suburban beach and also at a Yarra Valley spa and resort.
At the resort Grant stomped on her bare foot with his heel before knocking her to the ground, causing her to hit her head and elbow on the hard bathroom floor.
"I felt manipulated, betrayed and unable to feel safe," the woman said in her victim impact statement, read by police prosecutor Dale Andrews.
"My left foot took several months to heal ... I was unable to exercise for two months due to the pain."