Early years and Saint-Étienne Guarín was born in
Puerto Boyacá. In 2005, already a regular for
Envigado F.C. and the
Colombian under-20 national team, he joined
Boca Juniors of the
Argentine Primera División, where he spent the first six months in the youth team. Upon completion of his loan the
Buenos Aires-based club attempted to sign him on a permanent basis, but he instead chose to go on loan to
AS Saint-Étienne in August 2006. Guarín made his debut for the French side scoring twice in a
friendly against
RCD Espanyol, and gradually fought his way into the starting lineup as
the season closed. He first appeared in the
Ligue 1 on 14 October 2006 against
Olympique Lyonnais, and scored his first goal in a 3–1 victory over
Troyes AC. In April 2007, the deal was made permanent for four years.
Porto (2011) On 10 July 2008, Guarín agreed a four-year contract with
Primeira Liga club
FC Porto for an undisclosed fee.
Portuguese under-21 international
Paulo Machado went the opposite direction, on loan. During his spell he was used mainly as a
substitute, but managed to appear regularly; arguably, his most important goal came on 16 May 2010 as the team
renewed their
Taça de Portugal title, defeating
G.D. Chaves 2–1. In
2010–11, even after the departure of
Raul Meireles to
Liverpool, Guarín initially struggled to make Porto's starting XI. He was, however, a very important midfield element for the eventual national champions, playing more than 40 official games and scoring ten goals, including five in the
Europa League campaign, which also ended in conquest.
Inter Milan in 2014 Guarín joined
Inter Milan on 31 January 2012 for
€1.5 million, on loan, with the player replacing
Paris Saint-Germain FC-bound
Thiago Motta. The Italians also had an option to make the move permanent for €13.5 million in June. On 17 May 2012, a permanent deal was arranged, but for €11 million. Guarín scored his first official goal for the
Nerazzurri on 30 August, in a 2–2 home draw against
FC Vaslui in
the Europa League (4–2 on aggregate). In the group stage of the same competition, he provided all three
assists in a 3–1 defeat of
Neftchi Baku PFC. Again in the Europa League, on 21 February 2013, Guarín scored twice in a 3–0 away win over
CFR Cluj (5–0 on aggregate) to help Inter make it through to the
last 16. In the January 2014
transfer window, he was supposed to move to
Juventus FC in exchange for
Mirko Vučinić, but the deal ultimately fell through after the clubs could not reach an agreement. He declared he would not return if he was not allowed to leave, but eventually he reconsidered; it was later reported that he simply wanted to clarify his future with the club, stating that he never asked to leave and that he was confused as to why the situation was created. On 25 March 2014, Guarín agreed to extend his contract until 2017. On 14 September, as a second-half replacement, he scored in a 7–0 home win against
U.S. Sassuolo Calcio. At the start of the
2014–15 season, he began being used by manager
Walter Mazzarri as a
second striker. On 7 December 2014, in his 100th appearance for Inter, Guarín assisted
Mauro Icardi in the 44th minute of an eventual 1–2 home defeat to
Udinese Calcio. On 16 February of the following year, he scored twice after winning a first-minute
penalty kick in a 4–1 victory at
Atalanta BC, helping his team to secure the first away win in the league since December 2014.
Later career On 26 January 2016, Guarín joined
Shanghai Greenland Shenhua F.C. in the
Chinese Super League for a reported €11 million fee plus bonuses. On 26 September 2019, the 33-year-old
free agent moved to the
Campeonato Brasileiro Série A with
CR Vasco da Gama. Guarín agreed to a one-year deal at
Millonarios F.C. on 31 December 2020, again on a
free transfer. ==International career==