Michael Jordan may be the overall GOAT in the NBA, but Tim Duncan is widely accepted as the greatest power forward of all time. Duncan's legacy is incredible, he won an NBA title in 3 different decades, totaling 5 during his career and establishing the Spurs as a dynasty in the league for over 15 years. Duncan is known as the Big Fundamental, his play was as surgical and effective as any player in league history.
While many of the players that came after him were in awe of Michael Jordan, Tim Duncan was not one of them. He spoke in 1998 about respecting MJ but not being impressed by him. Well, the same wasn't true for Michael, who once named Duncan among the Top 4 players in the league while speaking at a training camp just after his second retirement in 1998 (via Essentially Sports).
“We got a lot of talented players." MJ first named Grant Hill, then Kobe Bryant, and even Shaquille O’Neal, but the next one was very unexpected. He said, “You can go with Duncan. Don’t sleep on Tim Duncan. I would think he is probably the most fundamental all-around big man.”
Duncan was always expected to be good, having been drafted No. 1 overall, but nobody could have seen him achieve the level of dominance that he did. In 1999, the season after MJ had retired for the 2nd time, Duncan went on to lead his Spurs team to the NBA championship, which would be the first of 5.
4 more followed, along with multiple MVPs, Finals MVPs, and numerous selections to the All-NBA First Team and the All-NBA Defensive teams. Duncan was a quiet assassin, never flashy off the court but lethal on it, and his fundamentals, which MJ had pointed out, were exactly what made him the implacable and relentless winning machine that he was during his prime in the NBA.