The Whiteboard: 5 breakout NBA seasons we didn’t see coming

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I like to joke that I’ve reached a new stage of sports fandom. With all the crap going on in the world outside arenas, I’m just looking for joy inside them. I used to root for teams and players who resonated with me in some way. Now I root for every team to go 82-0 and every player to maximize their potential. The weird thing is I’m not really disappointed any more often than I was before, but I feel a lot better about the energy I’m putting out into the sports world.

That’s why I’ve been taking so much enjoyment from the surprising starts by the players below. Whether it was a jump from fringe player to rotation piece or fringe star to superstar, these breakouts were hoped for but still delightful surprises.

Keldon Johnson, San Antonio Spurs

Looking for a potential breakout player on the Spurs’ roster this offseason would probably have led most people to Lonnie Walker (becoming a full-time starter) or rookie Devin Vassell (an elite 3-and-D prospect). Instead, Keldon Johnson has been the biggest surprise.

Johnson has started all seven games for the Spurs after appearing in just 17 games as a rookie, with a single start. And by this time next week, he will likely have played more minutes than he did all of last season. Johnson’s per-minute numbers were impressive as a rookie but they came in such a small sample, skewed heavily by garbage time, that it was hard to take them as too predictive. But this season, in nearly 30 minutes per game playing mostly at the 4, he’s averaging 15.1 points, 8.0 rebounds, 2.6 assists, 1.3 steals and 0.7 blocks, shooting 47.6 percent from the field and 41.7 percent from beyond the arc.

That Johnson has been able to sustain efficiency in a significantly larger and more meaningful role is even more impressive when you consider the context. He’s 6-foot-5 and 220 pounds and the players he’s spent the most possessions guarding this season are LeBron James, Zion Williamson, Dillon Brooks and Pascal Siakam. At the other end, the players he’s been defended by most frequently are Anthony Davis, Kyle Anderson, LeBron and Zion.

So we have a 21-year-old, second-year wing, sustaining tantalizingly and efficient production while moving into the starting lineup. And he’s doing it by moving up a position, holding his own against players who hold considerable size and strength advantages against him. The Spurs are still lavishing minutes on veterans like DeMar DeRozan and LaMarcus Aldridge and even that might not be enough to get them back in the playoffs. But their young core of Dejounte Murray, Lonnie Walker and, now, Keldon Johnson is looking more and more impressive.

Collin Sexton, Cleveland Cavaliers

Sexton had a surprisingly effective rookie season, the kind that made you wonder if the numbers were simply a mirage of playing on a rudderless rebuilding team where he could dominate the ball as much as possible. He followed that up with a quietly improved second season, demonstrating he could put up numbers regardless of the context but leaving lingering questions about whether he could contribute in the same way on a winning team.

Now, in his third season, the Cavaliers are a surprisingly frisky 4-3, with wins of Atlanta and Philadelphia, and Sexton is looking like a star. He’s averaging 25.7 points, 3.4 assists, 2.0 rebounds and 1.4 steals per game, shooting 55.1 percent from the field and 54.2 percent from beyond the arc. That 3-point percentage is certainly going to regress a bit but any lingering concerns about low volume and whether he’s really an outside shooter have been answered. He’s now made 39.8 percent of 575 career 3-point attempts and even if he’s not quite an elite outside shooter, he’s certainly a very good one and someone defenses need to account for.

The most important development for Sexton, however, has been his improvement inside the arc. His field goal percentage within three feet of the basket and from 3-10 feet from the basket has increased every season, as have his numbers on pull-up jumpers inside the arc. There are still plenty of areas in which he can improve (playmaking and defense) but he’s establishing himself as an indispensable three-level scorer.

Jaylen Brown, Boston Celtics

Jaylen Brown was already a borderline All-Star but he’s taken his game to another level for the Celtics this season. The key to his value is bringing a bit of everything to the table and taking nothing off of it but his improvement as a self-creator this year is one of those variables that gives the Celtics’ offense a whole new dimension.

Brown has always been adept at working off the ball but he’s been particularly effective this year in secondary actions, particularly coming off screens and in dribble hand-offs. He’s been unsustainably fantastic as a pull-up shooter (an effective field goal percentage of 69.3) but even significant regression there leaves him in great shape.

Perhaps the most important data points are that he’s averaging 26.9 points and 3.6 assists per 36 minutes, with a 59.4 effective field goal percentage in the 89 minutes he’s played without Tatum this year. His most frequent running mates in those minutes have been Semi Ojeleye, Daniel Theis, Grant Williams and Payton Pritchard. His ability to act as the engine for the second-unit offense has helped Boston weather the loss of Gordon Hayward and the absence of Kemba Walker and should only make them more dangerous when the playoffs roll around.

Lu Dort, Oklahoma City Thunder

Dort made a name for himself with incredibly stout defense against James Harden in last year’s playoffs but his offensive struggles — 7-of-38 from beyond the arc in the first five games of the series — were noticeable. The Rockets often opted not to guard him at all beyond the arc, crowding the paint and daring him to shoot. It’s the kind of circumstances that can chip away at the confidence of a young player, but Dort has responded. He was 6-of-12 on 3-pointers in the Thunder’s Game 6 loss and he’s hit 14-of-31 (45.2 percent) through six games for the Thunder.

Dort’s offensive responsibilities are still entirely complementary — 65.1 percent of the offensive possessions he’s used this season have come in transition or as a spot-up shooter. But he’s averaging 14.5 points per game on a 63.0 true shooting percentage. Throw in his defensive value and you’ve got a high-level role player that no one is scheming off the floor in a playoff series.

Tobias Harris, Philadelphia 76ers

Tobias Harris is a known quantity at this point and I’m not sure what he’s doing this year really qualifies as a “breakout.” But it’s worth pointing out — that after a terrible playoff series and an offseason of hand-wringing about his limitations and his enormous contract — he’s shooting a career-best 47.2 percent from beyond the arc and has racked up a combined 18 steals and blocks and seven games. Per 36 minutes, he’s averaging more than twice as many blocks and steals combined as he did last season. Philadelphia’s defense has been sensational and his energy at that end has been a big part of it. For a player this established to put so much focus into addressing a specific weakness is always fun to see.