In France Metsu spent over a decade as the manager of five different clubs in France before his first foray overseas as a football manager in the year 2000. After retiring as a player with
Beauvais in 1987, Metsu took up the youth team manager post with Beauvais in the same year. In 1988, he guided the Beauvais youth team to the runner-up position in the
Coupe Gambardella. From 1988 to 1992, he was the manager of Beauvais's senior team, which was in
Division 2 throughout his tenure there. In the 1988–1989 season, it reached the quarter-finals of the
Coupe de France for the first time in its history, where it lost to
Auxerre 2–1 on aggregate. Metsu guided Senegal to seal a spot in the
2002 World Cup finals for the first time in its history. They were expected to finish at the bottom of
Group A, which also contained
Denmark, two-time winners
Uruguay and 1998 champions
France. When the 2002 World Cup finals started, 21 of the 23 players in the Senegal national squad were playing with French clubs. Some members of the French team, as well as high-profile players of other teams, publicly dismissed the Senegalese. In a passionate speech to his team before the opening match of the tournament (
France versus Senegal), Metsu used the disparaging comments to stir his players. Metsu's psychological approach to the game led him to encourage Senegal's players to focus on France's weaknesses rather than their strengths; he used videos to show the Senegalese players all the weaknesses of the French players. Senegal pulled off a major surprise by beating the reigning
world and
European champions 1–0, with
Pape Bouba Diop scoring the only goal. "By concentrating five players in midfield, my friend Metsu concocted a nice plan. Individually and collectively, we could not find a solution. Senegal were better than us," conceded the France team manager
Roger Lemerre, who was magnanimous in defeat. "When I read them
Pelé's remarks that Senegal was the weakest team of the group, I immediately noticed a revolt in their eyes. I knew they were going to fight like lions," Metsu told the Nigerian newspaper
Vanguard later that year. After Senegal had defeated France in the opening match of the 2002 World Cup finals, Senegalese president
Abdoulaye Wade declared a national holiday. When the Senegal national football team returned to
Dakar following their exit from the 2002 World Cup finals, they were given a heroes' welcome. Metsu's connection to the country had been sealed when he married a Muslim by the name of Rokhaya 'Daba' Ndiaye, one day after he had converted from Christianity to
Islam in Senegal. She changed her name to Viviane Dièye Metsu after the marriage. After his conversion to Islam, he called himself
Abdulkarim Metsu and a fair part of the Senegalese press addressed him as
Abdulkarim. Metsu was mostly described in Senegal as a coach who inculcated the culture of courage and relentlessness in the Lions of Teranga, which subsequently influenced the junior ranks and the nation's club sides. Metsu brought a new spirit that inspired the nation's football and aroused young talent to see themselves as giants anywhere. He coach the club to win the re-branded
2002–03 AFC Champions League(its maiden title), and completed a double by winning the UAE Football League in the same year. Al Ain retained the UAE Football League title in 2004. This led to a host of offers for the Frenchman, who left Al Ain FC in May 2004 to join the Qatari club
Al-Gharafa in July 2004 as manager, to the resentment of Al Ain FC. Metsu was eventually forced to pay a fine for breach of contract. Metsu's overall record with the UAE was 13 wins (11 official), 9 draws (3 official) and 20 losses (8 official) in 42 matches (22 official), scoring 47 goals and conceding 59.
Al-Gharafa (second spell) Metsu did not have to wait long for a new job. He was appointed the manager of
Al-Gharafa in March 2011 on a three-year contract, returning to the club that he had guided to win the
Qatar Stars League in 2005. His club won the
2011 Qatar Crown Prince Cup in April 2011. Metsu was sacked from his post on 15 March 2012, just one year into his contract, due to poor results including a disheartening 5–1 home defeat to
Al Rayyan that caused the team to drop to seventh place in the Qatar Stars League standings.
Al Wasl Metsu was contacted by the
Senegalese Football Federation (FSF) in February 2012 about his possible return to the manager post of the
Senegal national football team. but it was eventually filled by
Manuel José. On 12 July 2012, Metsu was named as the new
Al Wasl FC head coach, replacing
Diego Maradona, who had been sacked two days earlier. On 26 October 2012, he resigned from Al Wasl after being hospitalised in
Dubai due to
stomach cancer. ==Death and funeral==