Prior to this season striker Batt spent the best part of two years on the sidelines with a knee problem, and recently had a spell on loan at Leyton Orient to build up his fitness.
But he was recalled by manager Kenny Jackett last week and climbed off the bench to hit the late winner as Millwall beat Watford 1-0 to move four points clear of the drop zone.
"You could tell by my celebration I was quite excited by the goal," he said.
"It's an important goal for the team and a massive three points going into the final few games of the season.
"I've had a lot of lows but the highs have outweighed them and that was another achievement to add to the list."
The Lions head to Huddersfield on Saturday knowing another win should see them safe.
Batt added: "It's been tight from top to bottom this year and looking at the points we are still four points off. It was a massive win and we have to back that up on Saturday.
"I don't want to predict anything though, the teams at the bottom keep picking up points so we need to keep winning games."