SANTIAGO - The latest installment of one of South American football's fiercest rivalries plays out at the Copa America on Monday when hosts Chile face Peru with a place in the final at stake.
Chile's Arturo Vidal celebrates at the end of the Copa America match against Uruguay, in Santiago, on June 24, 2015
Matches between the two neighbors are known as the "Clasico del Pacifico" and are played against a backdrop of historical enmity that dates back more than a century to the 1879-1883 War of the Pacific.
Chile and Peru also fought a long-running legal battle over the two nations' disputed maritime border.
On the football field, at least, the rivalry began in 1935, but the animosity pre-dates that first encounter by several decades.
Most famously, differences of opinion remain to this day over which country is responsible for the invention of the bicycle kick.
Chileans say they invented it in a 1914 match, christening the overhead volley as "La Chilena".
Peruvians see it differently, arguing that in fact it was first tried in the port city of Callao in the late 1800s, being given the name, "La Chalaca".
More recently, several matches between the two sides have entered folklore.
In 1977 Peru ended Chile's hopes of qualifying for the 1978 World Cup; Chile had inflicted the same misery on Peru in qualifiers for the 1974 tournament.
- Stronger pedigree -
Chile have the stronger pedigree in recent tournaments, qualifying for the last two World Cups, reaching the last 16 in 2014. Peru has not qualified for the World Cup since 1982.
Chile will start as clear favorites for Monday's semi-final as they aim to take another step towards ending their 99-year wait for Copa America glory.
However the hosts are nervously awaiting the outcome of a disciplinary case opened against key defender Gonzalo Jara on Saturday over his lurid off-the-ball assault on Uruguay striker Edinson Cavani during the quarter-finals.
Photos and camera footage clearly showed Jara attempting to shove a finger into Cavani's backside shortly before the Paris Saint-Germain star retaliated and was sent off.
CONMEBOL confirmed Saturday a case had been opened against Jara, with a decision expected sometime before Monday's semi-final. Sources have indicated Jara could face a tournament-ending five-match ban.
Any suspension of Jara, who has formed an effective partnership with Inter Milan's Gary Medel, will give Chile coach Jorge Sampaoli a major headache.
"Jara is crucial," said Chile's reserve goalkeeper Paulo Garces on Saturday. "Hopefully he will be available."
Chile face a Peru side which is brimming with confidence after recovering from a 2-1 defeat in their opening game against Brazil to reach the last four.
Los Incas swept aside Bolivia in the quarter-finals 3-1, with Brazil-based striker Paolo Guerrero scoring a hat-trick.
Flamengo forward Guerrero, who has spent the past three years in Brazil after spells in Germany with Bayern Munich and Hamburg, is on course to be the tournament top scorer following his superbly taken treble against the Bolivians.
Peru also have one of the players of the tournament in their ranks, the speedy and skilful winger Christian Cueva, who scored against Brazil in the opening match and played a starring role against Bolivia.