The Portugal international, who scored on his debut in another 5-0 win over Real Betis at the weekend, was in fine form against the Belgians, who are returning to Europe’s top flight for the first time in 65 years.
Barca boss Xavi showed Antwerp no mercy as he brought Ilkay Gundogan and Raphinha into his starting line-up and watched his side predictably dominate the opening exchanges at the Nou Camp.
It took just 11 minutes for Felix to make his mark as he cut in from the left and blazed the opener past visiting keeper Jean Butez.
Felix turned provider in the 19th minute when he floated in a wonderful cross and experienced striker Robert Lewandowski dived in at the far post to send home Barcelona’s second.
A great start continued for Felix, who featured for Chelsea last season but was deemed surplus to requirements and instead found himself on loan from Atlético Madrid to the Nou Camp.
Antwerp’s top-flight nightmare continued as the visitors made it 3-0 four minutes later, Raphinh’s cross was cut out by Jelle Bataille and flew past Butez and wide of the far post.
Barca were on cruise control but should have extended their advantage before half-time as Raphinha saw Buteze try to stop from close range and then Alejandro Balde selfishly fired past a lurking team-mate.
But it was all academic as the hosts continued their one-way traffic after the break and went 4-0 up after 54 minutes when 19-year-old Gavi fired home after Lewandowski’s work had sparked another Barcelona attack.
The irrepressible Felix grabbed his second of the night in the 66th minute when he headed home from Raphina’s cross in what proved to be the final goal of an agonizingly one-sided game.
Xavi introduced 16-year-old Lamine Yamal towards the end of the game, making the Spain international Barcelona’s youngest player in the Champions League.
Yamal also became the second youngest player in the history of the tournament, beaten only by Borussia Dortmund’s Youssoufa Moukoko.
Barcelona player ratings (4-3-3)
GK: Marc-Andre ter Stegen – 6/10 – Genuinely may not have touched the ball before a thoroughly impressive double save with 15 minutes to go.
RB: Joao Cancelo – 7/10 – Rarely tested defensively and brought some real flair in attack. A rabona cross was one of several moments which caught the eye.
CB: Jules Kounde – 7/10 – Stuck to Vincent Janssen like glue and didn’t give the prolific striker any space.
CB: Andreas Christensen – 6/10 – Didn’t stand out as much as his partner but that’s hardly unsurprising on such a quiet night. Did his job and that’s it.
LB: Alejandro Balde – 6/10 – Balde’s final ball wasn’t up to scratch here. The left-back got in so many good positions but it always felt like he should have been doing better.
DM: Frenkie de Jong – 7/10 – With defending not a top priority in a game like this, De Jong was regularly flying forward and causing real problems.
CM: Ilkay Gundogan – 7/10 – His elite movement was simply too much for Antwerp to handle. Got the assist for Felix’s opener.
CM: Gavi – 7/10 – A scrappy first-half showing saw Gavi booked for repeated fouling but the youngster calmed himself down and even added a goal before being withdrawn.
RW: Raphinha – 6/10 – Wasn’t particularly involved in Barcelona’s best moments but still proved to be an occasional threat. A nice cross for Felix’s second.
ST: Robert Lewandowski – 7/10 – Took his goal predictably well. Proved to be a reliable outlet for those around him. An experienced showing.
LW: Joao Felix – 9/10 – A thoroughly impressive performance. Dominated proceedings in the first half with a lovely goal and a delightful assist, and headed home a second goal to cap off a glorious outing.
SUB: Oriol Romeu (58′ for De Jong) – 6/10
SUB: Fermin Lopez (58′ for Gavi) – 6/10
SUB: Ferran Torres (68′ for Raphinha) – 6/10
SUB: Lamine Yamal (68′ for Felix) – 7/10
SUB: Sergi Roberto (76′ for Cancelo) – 6/10
Subs not used: Inaki Pena (GK), Ander Astralaga (GK), Marcos Alonso, Inigo Martinez, Marc Casado
Xavi – 8/10 – While his side were always heavy favourites, Xavi will have been delighted with how things played out here. Got the balance of his team right against a side who were focused on defending and managed to rest some of his big names when the job was done.