January 21, 2021 is the 21st day of the 21st year of the 21st century. For San Antonio Spurs fans, this only means one thing: Tim Duncan Day.

Duncan, who memorably wore the No. 21 throughout a decorated career with the Spurs, called it a career in 2016. Since then, he's become a yardstick for consistent excellence and total professionalism.

The folks on the mean streets of Twitter joined in on the fun as they celebrated unofficial Tim Duncan Day (h/t Marilyn Dubinski of Pounding The Rock).

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Duncan is clearly an all-time great, giving everything he had for the Spurs, the only team he played for in his illustrious 19-year career. Drafted as the first overall pick in 1997, he immediately transformed the fortunes of the Silver and Black. The soft-spoken 6-foot-11 big man went on to win Rookie of the Year, All-Star MVP, regular season MVP twice, and Finals MVP thrice. The Big Fundamental is a 15-time All-Star, 15-time All-NBA Team member, 15-time All-Defensive Team member, and most significantly, a five-time NBA champion.

Duncan, who is now an assistant coach with the Spurs, finished his legendary career with all-around averages of 19.0 points on 50.6 percent shooting, 10.8 rebounds, 3.0 assists, and 2.2 blocks. He is widely regarded as one of the greatest players in NBA history and is considered by many as the top power forward ever.

For all of his valuable contributions, Tim was inducted into the Hall of Fame in 2020 as a first-ballot inductee, which means he was enshrined in the first year of his eligibility.

Happy Tim Duncan Day!