Martín Gastón Demichelis (born 20 December 1980) is an Argentine footballer who plays for Málaga CF in Spain, mainly as a central defender – he can operate as a defensive midfielder on occasion. A tough-tackler, Demichelis spent most of his professional career with Bayern Munich in Germany (seven and a half years), winning 11 major titles with the team. He also competed in his country – with River Plate – and Spain.

River Plate

Born in Justiniano Posse, Córdoba, Demichelis started playing professionally in 2001, with Buenos Aires-based Club Atlético River Plate, having arrived at the club's youth system three years earlier.
He made his first-team – and first division – debut on 2 September 2001 in a game against Estudiantes de La Plata, scoring his only goal for the team against Rosario Central.

Bayern Munich

Demichelis signed for FC Bayern Munich in the 2003 summer, for €4.5 millions. His first season in the Bundesliga was not very positive, as he suffered a number of minor injuries, appearing in only 14 league games (21 in total) as the Bavarians finished in second position; in early 2004, he appeared in his only game with the reserves, against Stuttgarter Kickers.

Under new coach Felix Magath, Demichelis became a regular starter for Bayern, appearing in 75 official matches in two seasons combined as the team won back-to-back doubles, achieving a total of four during his spell.

New Bayern boss Ottmar Hitzfeld successfully reconverted Demichelis from a defensive midfielder into a central defender. In 2008–09 he netted a career-best four goals in 29 games, but the title was lost to VfL Wolfsburg. However, the player often clashed with the new manager Louis van Gaal, starting immediately after the first matchday after being dropped from the starting XI for the 2010–11 opener, against Wolfsburg, with Demichelis requesting that van Gaal omit him from the squad altogether, which the coach did. The player thereafter voiced to the press that it would be probable that he and the club went separate ways.

On 29 October 2010, benefitting from a run of injuries in the squad, Demichelis made one of his last appearances for Bayern, heading home in a 4–2 home win against SC Freiburg.

Málaga

In late December 2010 Demichelis agreed a deal with Spanish club Málaga CF, initially until the end of the 2010–11 season, with the Andalusians retaining the option to extend the contract for a further two seasons. He rejoined former River Plate manager Manuel Pellegrini, and made his La Liga debut on 8 January 2011, scoring in a 1–1 home draw against Athletic Bilbao.

During his first four months with Málaga, Demichelis was sent off twice, but also started in all the matches he was available, being essential – as another January 2011 signee, Júlio Baptista – as the club eventually avoided relegation.

On 22 August 2012, Demichelis scored Málaga's first-ever UEFA Champions League goal, netting the opener in the 2–0 playoff home win against Panathinaikos FC (also the aggregate score).