In football, when a team scores a goal, it is wildly celebrated by players and fans alike. After all, the purpose of the game is to score more goals than the opposition. On the flip side, a solid defensive shift from the team that prevents the opposition from scoring is often overlooked.
Sir Alex Ferguson once famously said, "attack wins you games, defence wins you titles". Every team needs to have a strong defence that does not leak goals and that complements its attacking line.
Let us now take a look at the top 10 teams that have conceded the fewest goals in the 21st century.
Note: Only teams that have maintained their top-flight status in Europe's top five leagues during the 21st century are considered.
#10 FC Girondins de Bordeaux - 795 goals conceded
Ligue 1 side Bordeaux make a surprise appearance on the list ahead of the likes of Real Madrid, Arsenal, Borussia Dortmund and Inter Milan.
The club, established in 1881, is one of the oldest clubs in France and have won seven major honours since the turn of the century thanks in part to their mean defence that only let in 795 goals in twenty years of top-flight football.
Their most famous former player remains Zinedine Zidane, who won the first silverware of his illustrious career with the club in 1995 when he helped them win the UEFA Intertoto Cup.
#9 AC Milan - 767 goals conceded
AC Milan are the most successful Italian club in international competition winning 18 FIFA and UEFA affiliated trophies. Though most of them came during their Golden Era in the 1950s and 1960s, they once again reached their historical heights in the early 2000s.
They had some of the world's best players in their ranks during that period, including two Ballon d'Or winners in Andriy Shevchenko and Kaka. In defence, they had Paolo Maldini, one of the greatest defenders of all time and between the sticks, they had Dida.
Thanks to a solid squad and a shrewd manager in Carlo Ancelotti in the first decade of the century, they boast the best defensive record among all Italian sides in the 21st-century, shipping in 767 goals. Juventus' one season in the Serie B after the Calciopoli Scandal cost them a spot on this list.
#8 Liverpool - 753 goals conceded
In this list, we have some of the biggest clubs in the world and current Premier League champions Liverpool take the eighth spot. The Reds are the most successful English clubs with 43 major titles and though they are now renowned for their supreme attacking abilities, they have been equally competent at the back this century, having only conceded 753 goals.
They have also scored 1.79 goals on average since 2000, and their numbers are expected to go up in the coming years.
#7 Olympique Lyon - 751 goals conceded
It might come as a surprise that Olympique Lyon of all clubs have made it to this list but for a club that has enjoyed its most successful period in the 21st century, dominating the Ligue 1 in the first decade, their tally makes sense. They have conceded 751 goals across all competitions in twenty seasons, which is the second-best for a French club.
The club made appearances across all major competitions, including the Champions League but failed to replicate their domestic success at the European level, only making it up to the semi-finals of Champions League twice and Europa League once.