The Norwegian joined Rovers on loan from Manchester United last Thursday and the attacker showed promising signs despite the 2-0 loss at Ewood Park.
"I thought he did okay," said Berg to Radio Rovers. "Obviously it will take a little bit of time before he gets used to everything.
"But he showed in parts of his game that he can give us that little bit extra with his offensive runs in behind, he can take people on and get into scoring positions.
"He had two good chances, one a good effort and the other he should have hit the target to maybe give us a goal, but at least he is getting into the right areas and the right positions.
"He is a young lad, we have to make sure we work on his finishing to make sure we score goals with chances like that.
"He's got the potential, he's quick, he's strong, he is good technically, we just need to keep improving and keep working with him and the rest of the team."
Rovers are back in action this Wednesday night when Bolton Wanderers are the visitors to Ewood Park, kick-off 7.45pm.
Tickets are on open sale for the match priced in all areas at £15 for Adults and £5 concessions. Book online today at www.onerovers.co.uk
and collect your tickets from the Blackburn End collection point on the day of the game.