The Barcelona forward had a hand in all three of his team's goals, scoring one beauty himself, as the 2014 World Cup hosts at times gave an indication of why they are already considered one of the favourites to lift the trophy next summer.
Given the historic rivalry between these two nations, this was a friendly in name only and both Luis Felipe Scolari and Paulo Bento sent out strong teams with neither coach wanting to concede an inch.
Yet Bento had to make do without Cristiano Ronaldo - the Real Madrid forward did not travel to the US as he battles tendonitis - so it was left to another star of the world game to take centre stage on his own. Barcelona's £48.6 million recruit Neymar did not disappoint.
Having been subjected to some rather robust treatment - most notably from Bruno Alves, who got away with an elbow to the Brazilian's head early in the first half - Neymar delivered the perfect riposte to his aggressors.
First the 21-year-old took a corner for Thiago Silva to cancel out Raul Merieles's opener in emphatic fashion and then, just 11 minutes later, he took off on a mazy dribble that saw him beat four defenders before slotting home for his 26th international goal.
His efforts turned the game on its head after Portugal had started the stronger and deservedly taken the lead.
Merieles had already hit the base of the post with a stooping header before he did find the back of the net, taking a gamble by anticipating Maicon's back header to his goalkeeper Julio Cesar following a shot that was deflected high into the air. Merieles was duly rewarded as he snuck in and stabbed home.
Then Neymar, who had been booked early on for a shoulder barge that sent Pepe flying into the onrushing Patricio, allowed his skills do the talking.
His shot on 22 minutes was spilled by Patricio and Bernard wasted the rebound before Thiago Silva met his corner with a thumping header to level things up.
The former Santos player's slalom dribble soon followed, the final flourish past Rui Patricio in the Portugal net perhaps fittingly applied with Bruno Alves - he of the wayward elbow - one of four defenders left trailing in his wake.
Jo could have put Brazil further in the lead from close range just a minute later before new Tottenham recruit Paulinho twice passed up decent opportunities to increase Brazil's advantage.
Yellow-shirted fans among the 62,000-strong crowd - there were many of them - did not have to wait much longer for a third though, as Jo did finally get on the scoresheet soon after the restart.
The former Manchester City and Everton striker bundled the ball home from Maxwell's cross after the Paris Saint-Germain defender had been set scampering towards the by-line by a cute pass from that man Neymar. It was Jo's fifth goal in 10 appearances for Brazil.
After that Neymar's influence diminished as the inevitable substitutions came thick and fast, resulting in a far less cohesive - and entertaining - second half.
The star of the show himself was taken off in the dying embers of the match, the crowd affording him a well-deserved ovation as he made his way off, but his job was already done.
Portugal, lying a point adrift of Russia in their World Cup qualifying Group F, still have theirs to do, with crucial games coming up in October against Israel and Luxembourg.