Today marks exactly 21 years since a 17-year-old Lionel Messi made his debut for Barcelona. The appearance was a sign of things to come, as the Argentine icon not only etched his name into the club’s history books but also cemented his status as arguably the greatest player to ever play the sport.October 16, 2004, will forever remain an important date in the calendar of every true Culer. Messi made his first appearance in an official competition for Barca’s senior team in a LaLiga match against cross-town rivals Espanyol, coming on as a substitute in the 82nd minute for Deco, who is currently the club’s sporting director. Interestingly, the match was played at the Estadi Olímpic Lluís Companys, currently serving as Barça’s home ground. It was Espanyol's home ground at the time.Unlike other youngsters, Messi didn’t quite look the part during his early years in the Barcelona senior team, although he mesmerized opponents with his dribbling skills. He was initially handed the number 30 jersey, before swapping that for the No. 19 shirt ahead of the 2005/06 season. In 2008, Messi was handed the iconic number 10 jersey after Ronaldinho’s departure, a number that has remained synonymous with his glittering career.Words cannot describe how magnificent Messi’s time was at the Catalan club. The 38-year-old won every available trophy in the 21 years he spent at Barca, while complementing them with numerous individual accolades. While his manner of departure wasn't the one the club or player had wanted, Messi will forever hold a special place in La Blaugrana’s history.Celebrating Messi’s 21st debut anniversary, Barcelona posted an image of their most decorated player on X (formerly Twitter), inscribed with the date he made his debut for the club.“We had no idea what was coming,” Barcelona captioned the post.FC Barcelona @FCBarcelonaLINKWe had no idea what was coming.The major honors Lionel Messi won during his time in the Barcelona senior team (2003-2021) include 3 FIFA Club World Cups, 4 UEFA Champions Leagues, 3 UEFA Super Cups, 10 LaLiga titles, 7 Copa del Reys, and 8 Spanish Super Cups. He scored 672 goals and registered 303 assists in 778 appearances across competitions.LaLiga celebrates Lionel Messi’s debut for BarcelonaThe top flight of Spanish football, LaLiga, also commemorated Lionel Messi’s debut for Barca's senior team. Celebrating the date, LaLiga posted a video of Messi replacing Deco in the second half.“The beginning of the LEGEND. 🌟On a day like today, in 2004 and with 30 on his back, Leo Messi made his debut in LALIGA EA SPORTS,” they captioned the post.Lionel Messi currently holds the record for the most goals in LaLiga history, scoring 474 goals in 520 appearances.