Sergio Aguero got Argentina's Copa America campaign back on track on Tuesday, scoring the only goal as the tournament favourites battled to a 1-0 victory over historic rivals Uruguay.
Aguero bagged his second goal of the tournament with a typically brave diving header in the 56th minute after a niggly battle between the 1930 World Cup finalists in their 199th meeting. The result leaves Argentina firmly on course to top Group B, with only one game against tournament minnows Jamaica, who were beaten 1-0 by Paraguay in Tuesday's early game, remaining.
Uruguay's defeat means the 2011 champions must now beat the Paraguayans in their final match to be certain of clinching a place in the last eight, although they could still reach the knockout rounds as one of the best third-placed teams.
Argentina captain Lionel Messi, who had expressed his fury after the Albiceleste surrendered a 2-0 lead in Saturday's 2-2 draw with Paraguay, praised his team-mates for keeping their cool in an often spiteful encounter. "It was a tough match from their side. They didn't want to play that much," said Messi, who was subjected to a series of cynical fouls throughout.
"They were tough. They were hard on us. But we showed that we can also play that kind of game if we need to. Yet we tried to keep playing our game and that's how we found the goal through Kun (Aguero)."
A tense first half had seen Argentina dominate possession and territory but fail to break down a resolute Uruguayan defence.
The two best chances of the opening period both fell to Argentina, with Manchester United winger Angel Di Maria testing Fernando Muslera in the ninth minute with an angled shot that the Uruguayan goalkeeper needed two attempts to gather. Muslera was pressed into action again midway through the half, producing a superb one-handed save to deny Aguero after the striker met Messi's sublime cross with a downward header.
Tensions began to rise thereafter, with Argentina coach Gerardo Martino shown a red card by Brazilian referee Sandro Ricci in the 38th minute. On the stroke of half-time, tempers flared once more with Argentina enforcer Javier Mascherano booked for sliding through Uruguay playmaker Nicolas Lodeiro, who had earlier seen yellow for a wild challenge on Zabaleta.
Uruguay carved out their best effort in the opening minutes of the second half, Maxi Pereira uncorking a fierce shot that Argentina goalkeeper Sergio Romero did well to clear.
With Messi being shadowed at every turn, it fell to others to break the deadlock and the game-changing moment came courtesy of Javier Pastore on 56 minutes. The Paris Saint-Germain midfielder showed sublime skill to release Zabaleta down the right, and the full-back took one touch before whipping in a cross to the near-post, met by Aguero to head home.
Uruguay, who entered the tournament without Luis Suarez, who is still serving a suspension for biting Italy's Giorgio Chiellini at the World Cup last year, were largely devoid of inspiration in attack with striker Edinson Cavani anonymous. But the holders were left ruing a glorious chance to equalise against the run of play in the 75th minute, Diego Rolan blazing over the bar from six yards after Romero had parried away Alvaro Perreira's shot.
Paraguay edge Jamaica
In Tuesday's other game, Paraguay edged closer to the last eight with a 1-0 win over Jamaica. A freak goal from Edgar Benitez proved the difference, the striker unwittingly deflecting a hapless headed clearance by Jamaica goalkeeper Duwayne Kerr into an empty net on 36 minutes.
The win means Paraguay need only a draw against Uruguay to be sure of finishing second in the Group.