He also had a successful experience in Colombia with América de Cali, winning two league titles and being runner-up of three Copa Libertadores.

He has won four league titles in Argentina (with Vélez Sarsfield); as well as a second division championship and a Copa CONMEBOL with Talleres de Córdoba.

In 1981, he was loaned out to Sarmiento for the 1981 Metropolitano, but he returned to Boca for the Nacional where he played alongside Diego Maradona, scoring 8 goals in the championship.

In 1985, Gareca earned the eternal hatred of many Boca fans for transferring directly to their fiercest rivals, River Plate, along with Oscar Ruggeri.

However, unlike Ruggeri, his time with River was short, and the fans started losing that hatred, as he soon joined Colombian team América de Cali later in 1985.

In 1993, he joined Independiente for the last years of his career, making him one of a select band of players to have played for four of the most successful teams in Argentine football.

In 1999, he led them to their first major title, the Copa CONMEBOL, making them the first team in Argentina from outside the Buenos Aires and Santa Fe provinces to win an international competition.

[8] Taking over shortly before the 2015 Copa América, Gareca faced a difficult task to encourage an already demoralized Peruvian team to achieve some football feat and to prove his worthiness as coach.

This was the repeat of the 2011 Copa América and thus he got some good credits, although skepticism remained high due to previous experience with Sergio Markarián in the 2014 World Cup qualifiers.

Following the dented 0–2 away loss to minnows Bolivia, Gareca faced possible sacking,[11] however the pressure was relieved when the Bolivians were found to have fielded ineligible player and the result was forfeited to a 3–0 win for Peru away.

[14] Between the 2018 World Cup qualifiers, Gareca's Peru participated in the Copa América Centenario held in the United States, where the team produced a successful performance, including a famous win over powerhouse Brazil, albeit in a controversial style.

Peru demonstrated a brave performance, but was not lucky as the team crashed out of group stage following two defeats to Denmark and France, before grabbing a 2–0 win over Australia to gain its first three points after 40 years.

After losing to the Australian national team in a playoff for one of the 32 berths in the 2022 FIFA World Cup on 13 June 2022, Gareca stated "Sometimes things don't work out.

[23] He has been linked to a potential coaching position for Mexico, after this country's elimination from the group stage of the 2022 FIFA World Cup.