Lopez was ejected after hitting Acuna with his very first pitch, leading to the only run as the Atlanta Braves edged Miami 1-0 Friday night.
"We all know Acuna is a superstar," Lopez said. "We all know the things he does. You also don't want to put him on base because he's a guy that can steal 40-50 bases a year."
"But that was just a poorly executed sinker," he said. "The ball just ran instead of sinking, and unfortunately hit him, and that's not what I want."
The Marlins have a history of hitting Acuna. Miami pitcher Jose Urena was tossed after nailing him with his first pitch in 2018 and Lopez didn't last any longer.
Lopez was ejected for hitting Acuna in the back of the left arm, and manager Don Mattingly soon was tossed, too, for arguing on his pitcher's behalf. They stayed on the field for a couple of minutes to plead their case with umpires.
"It wasn't on purpose," Mattingly said. "We have zero issues with the Braves. We have zero issues with these guys. This is a past thing that happened three years ago."
Acuna said he wasn't sure if the Marlins were trying to hit him again or not.
"I don't know, to be honest, just because of how many times it's happened," Acuna said through a translator. "Whether it was or whether it wasn't doesn't matter to me. My primary purpose and focus is that the team won."
Acuna has been hit five times in 52 regular-season games against the Marlins, including three times with their first pitch of the day. He also got hit in a playoff game against Miami last year.
This time, Acuna advanced to third on Freddie Freeman's single and scored on a sacrifice fly by Ozzie Albies, the NL leader with 59 RBIs.
Miami pitching coach Mel Stottlemyre Jr. was tossed by crew chief Dan Iassogna for arguing about Lopez's ejection after Freeman's hit.
Iassogna defended his decisions on the ejections.
"I think if you followed baseball at all, you understand that there's history between this team and Acuna specifically, but there was no heads up in place, no formal heads up in place for us prior to this game," Iassogna said. "And understand this is one of the other things that we're tasked to do is to keep control of the game.
"And we felt, and I felt, that by ejecting the pitcher rather than putting a warning out, that would absolutely stop any retaliation or continuing to really start a beanball war throughout the game. And so we made the decision to eject. I ejected him, and we did not have a beanball war. Tonight, we had one ejection. We had one hit batter and we had an ejection."
Lopez didn't think his ejection was warranted.
"It was pretty confusing," Lopez said. "You could tell by how Donnie and Mel came out of the dugout. They were pretty shocked by it, too. It was just, I don't know. Like I didn't know how to react. I didn't know what to do. It just caught me by surprise. It stings."
Atlanta got just two hits and still won its third in a row.
Drew Smyly won his career-best fourth straight start for the three-time defending NL East champion Braves, who improved to 40-41.
The Associated Press contributed to this report.