The United States edition of the pre-season tournament went to Barca thanks to Lionel Messi, Ivan Rakitic and Gerard Pique in Miami on Saturday amid the growing uncertainty over Neymar's future at Camp Nou.
It was far from a friendly clash at Hard Rock Stadium as Barca and LaLiga-Champions League titleholders Madrid went head-to-head on American soil, the former storming out the blocks.
Goals from Rakitic and Messi put Barca 2-0 up inside seven minutes but Mateo Kovacic reduced the deficit shortly after and Marco Asensio equalised nine minutes before half-time.
Gerard Pique restored Barca's lead in the 50th minute as Barca beat Manchester City to the ICC trophy, while Madrid ended the tournament without a victory.
Sergio Ramos took to the field for the first time during pre-season as Zinedine Zidane named his strongest XI minus the absent Cristiano Ronaldo and Toni Kroos, with Gareth Bale, Marcelo, Karim Benzema and Luka Modric headlining the side.
Barca also fielded a strong line-up, Ernesto Valverde including Paris Saint-Germain target Neymar, Messi, Luis Suarez, Iniesta and Pique.
There was an early scare as Neymar hobbled off the field in the second minute with an apparent ankle injury but he made his way back onto the pitch as Barca broke the deadlock.
Messi dribbled into the box, cut past Modric and curled the ball past Keylor Navas, albeit with some help from a deflection.
It got better for Barca four minutes later when Rakitic drilled a low shot into the bottom corner of the net.
Neymar used the outside of his boot to flick the ball to Suarez, who dummied it through to Rakitic and the Croatian finished powerfully to leave Madrid stunned.
Out of sorts early, Madrid managed to halt Barcelona's momentum against the run of play after Kovacic arrowed a fierce shot past Jasper Cillessen in the 15th minute.
Neymar almost got in on the action following Suarez's run out wide but the Brazil international's shot went just wide of the post after his dizzying control to beat Raphael Varane.
Madrid continued to live dangerously as Messi weaved his way into the penalty area, however Navas was quick to deny the Argentine star.
But Madrid capitalised on the counter-attack to draw level in the 36th minute after Asensio played the ball to Kovacic and received it back before finishing coolly inside the near post.
Barca reclaimed the lead five minutes into the second half as Neymar and team-mate Pique linked up.
After a winning the free-kick, Neymar whipped in a teasing delivery and an unmarked Pique lost his opponent before volleying into the net.
It should have been a fourth for Barca in the 55th minute after Neymar rounded Navas but he fired wide following some fancy work from Messi, while Suarez was denied by the Costa Rican moments later and Samuel Umtiti had his shot cleared off the line.
At the other end, Isco drove forward and tried to find the bottom corner but Cillessen used his outstretched arm to keep Barca ahead.
The wave of second-half substitutions caused a lull in the match but Isco almost brought the game back to life when he forced Cillessen into another fine save.