Playing their first league game of the season at home to Odd Grenland, Rosenborg came away 3-0 victors, with Bendtner getting his name on the scoresheet.
Expectations have been high at the Trondheim club ever since the 29-year-old former Arsenal and Juventus striker, still highly rated in Denmark and Norway despite a rocky last few years in his career, confirmed his switch to Eliteserien last month.
Bendtner was banned from the national team by the Danish Football Association for 18 months in 2013 after being convicted for drink-driving and has not made an international appearance since 2015. Prior to signing for Rosenborg, he most recently played for Nottingham Forest in the second tier of English football, as well as German club Wolfsburg.
But Bendtner's maiden appearance in Norway suggested that the forward, who has played 74 times and scored 29 goals for his country, may still have something to offer at the top level.
The Dane has already said that he hopes a successful season in Norway could help him to return to one of Europe's bigger leagues.
“Maybe he has his best four or five years ahead of him. He knows that we score 65-70 goals per season, and thinks that will give him the ideal conditions,” Rosenborg coach Kåre Ingebrigtsen told TV2 Norway after signing Bendtner last month.
Regardless of how long the high-profile striker stays at the club, the atmosphere prior to the game at Rosenborg's Lerkendal stadium on Sunday was highly charged in anticipation of Bendtner's debut, reports Danish newspaper Politiken.
After a goalless first half, Rosenborg's new number nine opened the scoring when he rose to head in a cross, to the jubilation of the club's fans.
The Trondheim team added two more goals to run out easy 3-0 winners.
“Our fans have given me a great welcome, they sang all the way through the match, which made me happy. So it was a bonus to be able to give something back by scoring in front of them,” Bendtner said after the game, according to a report by Politiken.
Ingebrigtsen said that Bendtner's performance came as no surprise to him.
“He has a very high level, we've been able to see that in training. So we were completely relaxed,” the coach said.
Asked at the post-match press conference whether he had been nervous about his debut, Bendtner responded with the type of swagger he has come to be known for during his career as a player in England, Italy and Germany.
“Nervous? About what?” was the striker's response.