Playing without star duo Lionel Messi and Luis Suarez, the Catalans fell behind early only for new recruit Antoine Griezmann to step up and guide Barca to a routine victory .
Barcelona would try to make the most of the occasion after the game as they tweeted a photo of Firpo waving and displaying all five fingers in a subtle nod to the scoreline on the night.
The post didn't go down too well with Betis fans still reeling from defeat and the loss of their promising defender and Barca quickly realised the error of their ways.
"FC Barcelona wish to sincerely apologise for any offence caused to Real Betis and their supporters regarding a tweet sent out on Sunday evening," the tweet read.
"No disrespect was intended, but we were wrong to publish it on a night that was very special for Junior."
. @FCBarcelona wish to sincerely apologise for any offence caused to Real Betis and their supporters regarding a tweet sent out on Sunday evening. No disrespect was intended, but we were wrong to publish it on a night that was very special for Junior. https://t.co/JyvRDw7cuQ
— FC Barcelona (@FCBarcelona) August 26, 2019
Firpo himself is no stranger to social media controversy with the 23-year-old recently forced to explain crude tweets he sent out about Messi when he was a teenager.
Like Barcelona, Firpo has been quick to apologise and stressed the Argentine bears no ill will .
“It's something that doesn't matter and that I can explain without problem," Firpo told Mundo Deportivo .
"They are things that are done at 15 when nobody knows you and when you cannot think that this will have an impact years later.
"I have to apologise and I do it humbly and without problems."
Social media scandals aside, the Catalans got their La Liga campaign back on track against Betis after they had lost their league opener 1-0 to Atheltic Club.
Barcelona have started their season without Messi, who remains out with a calf strain, with Valverde stressing they won't be rushing the 32-year-old back into action.
"There wasn't a positive feeling. He hasn't had a relapse of the injury," Valverde said after beating Betis.
"We already said that we wouldn't rush any player. What we wanted to avoid was a relapse."