Raphinha and Fermin Lopez scored the goals, but the biggest moment for the home supporters came in the 63rd minute when Rodri was introduced for Raphinha.
The midfielder received a loud ovation as he made his first appearance in a Barcelona shirt following his summer move.
Rodri was delighted with his debut and the result, although he admitted he still needs time to reach full fitness.
"Very happy to play my first match, happy with the victory. Two out of two," Rodri said. "It's important to get some rhythm and adapt to this great team. First minutes and good feelings."
The Spain international has had a longer summer than usual and is still working his way back to his best after having limited training time.
"It has been a long summer, longer than usual. I need to quickly get up to speed. I've had very few training sessions," he said.
"These minutes have been very important to get some rhythm. This is where I wanted to be. Now it's time to work."
Rodri also highlighted Barcelona's quality and believes there is plenty more to come from the team.
"The best players in the world are here, and we have to be at their level," he said. "This team has significant room for improvement, and we're going to work towards that."
The experienced midfielder also showed his leadership qualities when discussing Lamine Yamal, who had been frustrated after being substituted against Elche.
"Lamine has been impressive. We tried to lift him up, and we saw the best version of him, even though he wasn't able to score," Rodri said. "The goals will come because the talent is there."
Rodri believes Barcelona's midfield options can also give Flick different solutions throughout the season.
"The most important thing is that we are all different. We give the coach different qualities," he said. "There is a great variety that allows us to have a lot of richness."
Barcelona will now look to build on their perfect start when they face Rayo Vallecano at Spotify Camp Nou on Monday.
