De Villiers was seen at the practice, coming ahead of skipper Virat Kohli and Chris Gayle.
Royal Challengers Bangalore will be bolstered by the return of star batsman AB de Villiers in their IPL clash against Kolkata Knight Riders here on Sunday.
"I think he is okay," Royal Challengers leg-spinner Yuzvendra Chahal said at the match-eve news conference on Saturday.
The South African was seen at the practice, coming ahead of skipper Virat Kohli and Chris Gayle, who joined the team in the second-half of their session.
If De Villiers returns, Travis Head will have to sit out.
De Villiers, who had already missed the first two matches of the season with a back injury, had a recurring back trouble that forced him to sit out of their previous match against Gujarat Lions.
In de Villiers' absence, Kohli returned to open with Gayle and they put together a 122-run opening stand to post the season-high 213/2 en route a 21-run win over the Lions.