The 22-year-old came under fire following Villa's 4-1 defeat to Stoke City on March 23.
Bacuna was also at fault for giving away a penalty in his side's loss to Manchester United last weekend.
"He is doing really well," the Birmingham Mail quotes Vlaar as saying. "It's not easy, I know that myself, and he's not even a right full-back originally. He is improving, doing good work and sometimes you have a less good game."
The Midlands outfit are currently 12th in the Premier League table with seven games left to play.