The gap between the two sides is now eight points, thanks to a gritty display from Messi and company to keep Atletico at bay.
Here’s how each player fared in Barca’s crucial win.
Sergi Roberto 7 – Looked untroubled at right-back, standing up well to the threat of Atleti’s attack throughout the game. The fact that much of the away side’s attacking play came down the opposite flank is a testament to Roberto’s solidity.
Gerard Pique 8 – Was absolutely immense in defence, repelling attack after attack. Will be disappointed not to have scored, passing up a couple of good opportunities from set-pieces.
Samuel Umtiti 7 – Marshalled Diego Costa and Antoine Griezmann well, winning his duels with both of the visitors’ star attackers.
Jordi Alba 7 – The Barca left-back usually wins plaudits for his attacking play, but on Sunday he showed his defensive prowess, standing up well to any forward play down his side.
Sergio Busquets 8 – Vintage performance from the midfielder as he helped his team weather heavy pressure in the second 45.
Andres Iniesta 5 – Was forced off early in the game with an injury, a sight which would have worried Barcelona management and fans. Never looked up to speed.
Ivan Rakitic 7 – Ernesto Valverde’s selection dilemma came down to Rakitic v Paulinho, and the Croat justified his manager’s choice in picking him. Neat and composed throughout.
Philippe Coutinho 7 – Not a performance that filled up the stat sheet, but the Brazilian was superb in the second-half, giving Barcelona a second wind with his running and trickery.
Luis Suarez 4 – Stood out more for his histrionics than his play. His headline moment was running into Atletico manager Diego Simeone on the touchline, although he came close to scoring with a late chip.
Lionel Messi 8 – Another game decided by a moment of Messi brilliance. It’s not easy to catch Atletico keeper Jan Oblak out, but the Barcelona wizard did exactly that with his free-kick.
Andre Gomez 5 – An up-and-down performance from the midfielder – as evidenced by the Nou Camp’s reactions, as fans took turns cheering him on and jeering him.
Paulinho 5 – Had little to do after coming on late in the game, although his running and hold-up play helped Barcelona see out the game.
Atletico Madrid were coming up on the rails in La Liga, Antoine Griezmann the most in-form player after hitting seven goals in his last two games, but then they came up against a certain mini-maestro named Lionel Messi.
Barcelona extended their lead in La Liga over Atleti to eight points – effectively nine given their superior head-to-head record – after some usual Messi magic broke down a stubborn defence deep in the first-half.
But aside from that sumptuous free-kick, which brought up his 600th goal for club and country combined, just how did Messi mastermind yet another win?
Goals – 1
Assists – 0
Shots – 5
Shots on target – 2
Passes – 57
Aerials won – 2
Key passes – 5
Dribbles – 5
Dispossessed – 8
Messi’s free-kick lit up a game that was dim for the most part due to Barcelona’s dominance of possession rubbing up against a rugged and disciplined Atletico.
The well-drilled away side had no special drill for Messi, however, who for the most part operated with freedom wherever he pleased – as his team’s ‘quarterback’ just ahead of the defence, on the left and right, and everywhere in between.
Atletico grew into the game as the second-half wore on and a marginal offside goal denied Kevin Gameiro an unlikely equaliser, but Barca continued to operate through Messi even if the chances were not flowing.
Ultimately Atletico could not stop the flow of points heading Barca’s way, as all it took was a second of inspiration from the Nou Camp’s greatest footballer.
Link-up with Coutinho – Much of the praise should go to Philippe Coutinho on this point, though Messi is clearly learning how to give such a mobile and fluid player – much like himself – room to breathe on his own.
Messi was happy to play second fiddle at times and play short, sharp passes to a onrushing Coutinho, who eerily looked like the Barca legend at times on the run with the ball. Perhaps Jorge Sampaoli should take this as a template as he tries – and fails to meld Messi and Paulo Dybala for Argentina.
Big game man – The only aspect of this match to make Messi’s highlight reel – or a ‘GIF’ for the modern man – will be the free-kick. But the fact that Messi needs just one chance to all but secure another game, another title for Barca never ceases to amaze. He has now scored five free-kicks this season, and it’s got to the point where you expect the ball to fly into the net.
Wastefulness – While criticism of Messi’s performance should be kept to a bare minimum, he was not razor-sharp in possession. The 30-year-old lost the ball eight times and in some promising areas, most notably by Antoine Griezmann who took him completely by surprise in the opening stages of the game.
Perhaps you have to give some credit to Atletico, rather than question Messi – after all, that goal was only the 13th that Diego Simeone’s side had conceded in La Liga all season.
21st min MISSED CHANCE Messi slips through the eye of the needle in characteristic fashion, but after beating three defenders, can only find the centre of the goal and a relieved Jan Oblak.
26th min GOAL Is brought down by Thomas Partey – and it proves a fatal mistake by the defender. Diego Costa, the tallest man on the wall, jumps for dear life but can get nowhere near to Messi’s free-kick as the vicious bend beats Oblak’s outstretched palm and nestles into the corner of the net.
32nd min INTERCEPTION Neither can you sleep on Messi when he’s without the ball. The Argentinian wins it back just outside the penalty box and only a desperate block stops Luis Suarez from firing in Barca’s second.
39nd min CREATED CHANCE Is released in midfield and drives at the heart of Atletico’s defence. He lays a simple pass to Sergi Roberto but the moves breaks down after his terrible cross.
77th min MISSED CHANCE The away side give the ball away in a dangerous area and Messi has all the time in the world to shape up and shoot, but hesitates enough for an Atleti body to come across his path.
This may not have been Messi’s most efficient performance of the season but may well go down as his most important, as he scored the goal that surely ends Atletico Madrid’s La Liga challenge – and crowns Barca’s.
Whereas Cristiano Ronaldo’s free-kick powers have waned with age, Messi is getting deadlier and deadlier – his latest slab of set-piece trickery was his third goal from a free-kick in three consecutive La Liga games, the first time he has done so.
All statistics are compiled using whoscored.com
Messi, 30, notched his 539th strike for the Catalans with a delicious free-kick against Atletico Madrid on Sunday. This figure is bolstered by a leading 61 goals in 123 appearances for La Albiceleste.
His astonishing exploits has seen him join Real Madrid rival Cristiano Ronaldo in passing the 600-mark for club and country. The Portugal icon did this in style with his second goal during last June’s Champions League-final triumph against Juventus.
In total, Messi has 373 La Liga goals, 98 Champions League goals, 61 international goals, five Club World Cup goals, three European Super Cup goals, 47 Copa del Rey goals and 13 Spanish Super Cup goals.
His first strike came in May 1, 2005’s 2-0 win against Albacete in La Liga, scooping the ball over the top of goalkeeper Raul Valbuena to become Barca’s youngest-ever goalscorer aged 17.