Before the season, I ranked the top 25 players in the NBA under the age of 25.

With more than two-thirds of the regular season in the books, a lot has changed. Not only have we gotten a good look at the 2021 draft class, we’ve also seen significant improvements among players from the 2017, 2018, 2019 and 2020 draft classes.

So I’m going to forgo my usual Tuesday column and re-rank the Top 25 under 25.

What’s new, who’s out and players who slipped

Since the season began, three players have “aged out” of the list: Devin Booker, Jaylen Brown and Jamal Murray (who turns 25 this week).

Three more dropped off the list after struggling this season: De’Aaron Fox and rookies Jalen Green and Jalen Suggs. 

Just missing the list are several promising players under 25, including RJ Barrett, OG Anunoby, Desmond Bane, Tyrese Maxey and Franz Wagner.

Injuries have significantly changed the outlook for top prospects Zion Williamson and Michael Porter Jr., but they are still in.

Miles Bridges, Onyeka Okongwu, Josh Giddey, Tyrese Haliburton, Jarrett Allen and Darius Garland are new additions to this list.

How we get our rankings

To qualify, players have to be in the NBA — while we love covering Scoot Henderson, Jabari Smith, Chet Holmgren and other top prospects outside the NBA extensively, they don’t qualify here. And we’re looking only at players who will be under the age of 25 at the resumption of the NBA regular season (February 24).

To get an accurate ranking, I combined two sources of information:

First, I used three analytics models (DARKO, LEBRON, and RAPTOR) to rate each player. Next to each player’s name, you can see his scores via the three models (D for DARKO, L for LEBRON and R for RAPTOR). Each plus-minus system measures the number of points a player contributes to his team’s offense and defense per 100 possessions, relative to a league-average player.

Second, I asked a handful of NBA GMs and scouts to rate each player under 25. For younger players, I asked them to think about the impact the players would have in the league by the time they are 24. 

This is especially important to understand for younger players like Evan Mobley and Scottie Barnes (both age 20). In some cases, they are not yet better than some of the 23- and 24-year-old players below them on the list. But they are projected to be. 

Using that methodology, here’s a look at players 11 to 25 on my list:

On Wednesday we revealed players 1 to 10.

25. Michael Porter Jr.

Denver Nuggets | 23 | Tier 3 | LEBRON: 0.41 | DARKO: 1.6 | RAPTOR: -0.2
Previous rank: 12

Concerns about Porter’s long-term health continue to make it tough to accurately grade him. 

In December, Porter underwent back surgery for the second time in his NBA career after nine subpar early-season games, which brought him up to only 125 games played since he was drafted four years ago. While he’s considered somewhat likely to return this season, NBA teams have been concerned about the health of his back for years — a major reason he dropped to No. 14 in 2018 rather than going near the top of the lottery — and those worries won’t disappear anytime soon. Given that, it’s difficult to rank him above the others on this list.

When healthy, Porter is one of the most electric scorers in the league, with a lethal jump shot that’s practically unstoppable given he is 6’10” and has a high release. On the other end, his defensive impact has been questionable, though he has the potential to be a force, especially on the boards.

24. Lonzo Ball

Chicago Bulls | 24 | T3 | L: 0.51 | D: 0.5 | R: 2.4
Previous rank: 25

Ball was in the midst of his best overall season when he injured his left knee. He underwent surgery in late January and is expected to return in March. Before the injury, Ball was shooting a career-high 42.3% from 3 and his play on both ends had helped the Bulls become a contender in the Eastern Conference.

While Ball is not exactly the Showtime point guard that Lakers fans hoped for when the team drafted him No. 2 in 2017, he's become one of the better all-around young players in the league. If he can stay healthy, he probably still has his best basketball ahead of him.