But the teenager insists he is determined to learn from one of the world's best players rather than become frustrated by the reduced opportunities.
The 19-year-old discussed his role under Hansi Flick, his relationship with team-mates and the challenge of establishing himself in a star-studded squad during an interview with COPE's El Partidazo.
Bernal acknowledged that he immediately understood the implications of Barcelona signing Rodri, but also recognised the opportunity to learn from a player he regards as the best in his position.
"I looked at it in two ways: first, I have the best defensive midfielder in the world and I can learn a lot from him. The second is that he was taking away many of my minutes," he said.
"The club gave me reassurance and that meant a lot because they didn't have to do that. They sign him and that's it. It's true that he takes minutes away from you. I take it well, I try to watch what he does and what he is like. He is a leader within the group. He is very easy to get along with.
"I'm 19 and he's 30. I have many years of my career ahead of me. It annoys me because I'm not going to get the minutes, but that's not something I want to dwell on now. I'm not letting it get into my head."
The midfielder's comments reflect the difficult balance facing a young player at a club competing for major honours. Rodri's arrival has strengthened Barcelona's options, but Bernal knows that opportunities will still come across a long season.
He also revealed that the club's senior figures made a point of reassuring him after the signing, helping him understand that his development remained part of their plans.
Bernal was also surprised by one of Flick's tactical decisions during Barcelona's recent match against Atletico Madrid, when Frenkie de Jong was deployed at right-back.
"I asked Frenkie and he told me he was going to play at right-back. I was surprised, but the truth is he played very well."
The teenager was asked about Barcelona's standing among Europe's leading teams and showed no hesitation in backing his own club, despite their defeat by Real Madrid.
"For me, the best team is Barcelona. It's true that we lost to Madrid, but one match doesn't determine that. For me, PSG aren't better either. If we play against PSG at home, do you think they would beat us? I trust that we can beat them further down the line. Honestly, if we're playing well and without injuries, we can beat them."
Bernal also spoke warmly about his relationship with Flick, describing the German as approachable and supportive. The coach sent him messages during his injury absence and when he was called up to the senior Spain national team.
"We have a very good relationship. He's very close to the players. He sent me messages when I was injured or when I went away with the senior national team. I don't speak any English and he speaks a little. If we have to discuss something, we usually have a translator."
His closest relationship in the squad is with Lamine Yamal. The pair have known each other since their earliest days in Barcelona's youth system and have remained friends throughout their development.
"I've been with him since pre-benjamín. We've always been friends, we get on very well. When you've played together for so many years, you become friends."
For Bernal, the challenge is to turn the experience of competing alongside established stars into an advantage. Rodri's arrival may make regular minutes harder to find, but the teenager is determined to use the opportunity to learn while continuing to fight for his place under Flick.