The Norwegian internationalist completed a six-month loan deal from Cardiff City on Monday and went straight into the squad for the first-leg of Celtic's Champions League third qualifier against Legia Warsaw in Poland on Wednesday night.
The 23-year-old former Molde forward played for Deila at Norwegian club Stromsgodset and is happy to play "anywhere up front", and it is that versatility which the Parkhead boss believes is crucial at this point in the season.
Speaking at the team's hotel in Warsaw, Deila said: "I know Jo Inge from the past, we worked together at Stromsgodset. He is a very intelligent player, he is a player who knows my systems, he can play all the four forward positions - the two wings, the No.10 and No.9.
"So I am comfortable and I know he will bring something new to the team. We don't have many options in the wide positions and it is very hard these days when there is so much time left before the window closes to get people in and get people who know the way we want to play, so Jo Inge is a perfect match in that matter."
Berget was surprised at the alacrity of his move to the Scottish champions and equally pleased to have been reunited with a manager he knows well.
"It happened pretty fast," he said. "I heard a couple of days ago that Ronny was interested and I am really happy that it worked out. I played for him for a year and a half, I know him well and he knows me. He wants to play football, entertaining football, the same as me.
"I have been in the qualification [rounds] before but have never played in the Champions League so hopefully I will be able to get there.
"That is the goal for the club and it should be a goal for the club as big as it is. This is a great opportunity for me, it is a great club and I hope it works well. It is up to me. It didn't really work out for me in Cardiff, I didn't play as much as I wanted to but hopefully it will turn around here."
Deila, in what is becoming a familiar way, straight-batted questions about other possible new signings, saying: "We are working very hard to improve the squad, working on different players.
"You need to have a list as you can't always get your first choice. But we have a good scouting department and we have a lot of options."
The Norwegian insists the squad he has at his disposal now is improving daily and was particularly impressed by the way Celtic dispatched Iceland side KR Reykjavik 4-0 in the second-leg of their second qualifier at Murrayfield to win 5-0 on aggregate.
"In the last game against KR Reykjavik we controlled the game and we were good when we lost the ball so I am pleased," he said.
"The passing has to be even better and the awareness and defensive marking, so we still have things to work on. But the players are working very hard and there is a lot of quality in the squad so I am very happy right now."