The 24-year-old playmaker signed a long-term contract with the Reds earlier this month after Liverpool agreed a £29m deal with Bundesliga side Hoffenheim.
I’m expecting us to be two fighters on the pitch battling together for the best for Liverpool
Coutinho has been a big hit on Merseyside following his £8.5m switch from Inter Milan in January 2013, and the midfielder was named the club’s player of the year in May.
Firmino, who scored seven goals and made 10 assists in 33 Bundesliga games last season, discussed his potential partnership with Coutinho.
“Philippe is a great person and has a big heart. He showed me his personal qualities during our time together at the Selecao,” Firmino told Liverpool’s website.
“I’m expecting us to be two fighters on the pitch battling together for the best for Liverpool, hoping that it will bring us the victories.”
The Brazil international added that his compatriot played a role in convincing the midfielder to make the move to Liverpool this summer.
“He was very helpful although it was ultimately my decision,” Coutinho added.
“I wanted to know more about how it works here and he had some very good things to tell me. He’s a great character and I hope we can nurture our friendship at Liverpool.”
Liverpool midfielder Coutinho scored five goals and made five assists in 35 Premier League appearances last term.
The 23-year-old has established himself as a key part of Brendan Rodgers’s side, and he penned a new contract earlier this year.
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