Everything goes from wrong to right for the hosts as Messi is allowed to roam and create in Argentina's 3-0 win against Costa Rica.
Lionel Messi and Argentina finally click at the Copa America
Argentina 3 // Costa Rica 0
CORDOBA, ARGENTINA // A reborn Argentina beat Costa Rica 3-0 to reach the quarter-finals of the Copa America in style courtesy of a brace from Sergio Aguero and another from Angel Di Maria.
Aguero, on from the start with the Manchester City striker Carlos Tevez benched in a revamped forward line, netted seconds from half time after the hosts had dominated the opening stages.
With Lionel Messi magnificently pulling the strings just behind the main strikers, the Atletico Madrid star Aguero made the points safe with a second goal seven minutes after the restart to take his tally at the tournament to three.
Di Maria then finished off the outclassed Ticos with the third just after the hour mark as Argentina joined Group A winners Colombia, Chile, Peru and Venezuela into the last-eight.
"Now another Copa is starting — we more than anyone want the best for Argentina," said Messi, thanking fans for getting behind a side they had brutally criticised prior to their final group game.
"This was a real tonic — just what we needed," said Aguero.
"We played very well and got the goals — but the main thing was we gelled as a team. Now we have to keep it up."
Javier Pastore, a late substitute for the profligate Gonzalo Higuain, who could have at least doubled the margin, agreed.
"That was a really important win and a good team performance — our attitude was spot on," he said.
Sergio Batista, the coach, was under huge pressure to deliver a win and secure passage to the next round with the hosts seeking their first major trophy since 1993.
And after their slow start he rang the changes with Tevez and Ezequiel Lavezzi benched and Higuain brought in as a classic centre-forward allowing Messi to concentrate more on his string pulling out of the immediate firing line.
Where Messi in particular was concerned, the plan worked like a dream, as the Barcelona man was involved in almost every move, tearing Costa Rica's defence to shreds with his incisive passing and weaving in and out.
Argentina's revamped forward line lay siege to Leonel Moreira's goalmouth from the off, with Real Madrid's Higuain firing a snap shot well wide on the turn before Messi, having hit the woodwork with a free-kick, drove just over.
Aguero then drilled a low effort just past the post as the one-way traffic continued before Messi went off on a run down the right, only for Aguero to blast off target after taking his through pass.
Again, Messi, the world player of the year, facing huge popular criticism for his country's poor start following draws with Bolivia and Colombia, ran at the Costa Rican defence, finding Higuain, who drove wildly over from barely ten yards out.
But the dam had to burst and it finally did seconds before the interval.
Fernando Gago fired a drive goalwards which Moreira could not hold and Aguero, following up, dinked the ball home.
The second half continued in the same vein and it was 2-0 on 53 minutes as Messi teed up another neat finish for Aguero.
Higuain had an effort ruled out for offside, then should have had a penalty when he appeared to been held back inside the box and fired over once more after yet another pass from Messi, who was carving apart the Costa Rican defence almost at will.
And it was Messi again who set up the killer blow, sliding a perfectly-weighted pass through for Di Maria to blast home left-footed for a 3-0 lead without even breaking stride.
A 54,000 crowd — which included 1978 World Cup hero Mario Kempes, visiting a stadium named after him — gave Messi a huge ovation at the end as the Barca man and the team renewed their covenant with the delirious fans.
"Lionel knows how to overcome these situations, he has personality to overcome them and today he showed it on the field," Batista said. "He played a tremendous match."
Argentina improve to five points in three matches and finished second in Group A.
Colombia finish first with seven points. The top two teams in each of the three groups advance, along with the best two third-place teams.
Colombia will now play one of the best third-place team and Argentina will face the second-place team in Group C: either Chile, Peru or Uruguay. Group B and C will be settled tonight and on Wednesday.
Despite the defeat, Costa Rica are not eliminated but must rely on Brazil and Paraguay both losing their final group games.