Kawhi Leonard is the last major free agent standing, and he holds the keys to the NBA

The NBA world is still waiting on Kawhi Leonard's free agency decision.

If Leonard re-signs with the Toronto Raptors, they would likely be considered the favorites in the Eastern Conference, while the Western Conference would appear to be wide open.

If Leonard leaves the Raptors for either the Los Angeles Lakers or Los Angeles Clippers, as has been rumored, both teams could stake a claim as the best in the West, while the East may suddenly be open.

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When NBA free agency opened at 6 p.m. ET on Sunday, many of the league's biggest dominoes fell, beginning with Kyrie Irving and Kevin Durant joining the Brooklyn Nets.

From there, the league landscape seemed to change: Kemba Walker joined the Boston Celtics, Al Horford joined the Philadelphia 76ers, D'Angelo Russell became a Golden State Warrior, The New York Knicks struck out, the Utah Jazz and Indiana Pacers made big splashes, and the Milwaukee Bucks doubled-down on their roster.

However, perhaps the biggest domino is yet to fall: Kawhi Leonard.

It's early in free agency, but considering how quickly the rest of the league moved, Leonard's slow-moving decision appears to have at least three teams in limbo: the Toronto Raptors, Los Angeles Lakers, and Los Angeles Clippers.

It feels as though wherever Leonard lands, it will shift the league.

If Leonard stays in Toronto...

The Raptors are the reigning NBA champions and would figure to be the title favorites in 2019-20 if Leonard re-signs.

The Raptors' core is still intact, and free agent guard-forward Danny Green is reportedly waiting on Leonard's decision before he decides free agency.

The Raptors running it back another season could affect the rest of the Eastern Conference. The Bucks mostly retained their core but lost young guard Malcolm Brogdon to the Indiana Pacers. Barring another leap from Giannis Antetokounmpo, it's unclear if they can drastically improve, though they figure to remain a contender.

The Philadelphia 76ers could once again be contenders after retaining Tobias Harris, signing Al Horford, and landing Josh Richardson from the Miami Heat in a sign-and-trade for Jimmy Butler. But questions about their fit and shooting will persist.

After that, there is a drop-off in the East. The Nets figure to contend for the playoffs will be without Kevin Durant for a year. The Celtics landed Walker but lost Irving and Horford. The Pacers could compete for a top-four spot, but their ceiling will be dependent on the return of Victor Oladipo.

Meanwhile, in the Western Conference, the Lakers and Clippers could be left scrambling. The Lakers desperately need to fill out their roster but have been waiting on Leonard. If Leonard turns them down, they will have a limited pool of players to sign with their $32 million in cap space.

The Clippers, once considered the favorites to sign Leonard, could ultimately sign short-term deals to roll their cap space over. With the biggest players in free agency mostly off the board, missing out on Kawhi Leonard would ultimately mark a big swing and miss by the Clippers.

If neither LA team lands Leonard, the Western Conference appears to be wide open, with the Rockets, Nuggets, Blazers, Thunder, Lakers, and Jazz all staking credible claims as the best team in the conference.

If Leonard joins the Clippers or the Lakers

It would be hard not to consider the Lakers the championship favorites if they added Anthony Davis and Leonard to LeBron James in the same offseason. Though signing Leonard would limit their ability to fill out the rest of their roster, they would boast three of perhaps the seven best players in the entire NBA.

If the Clippers signed Leonard, they, too, would be able to contend for the Western Conference. The Clippers won 48 games last year and pushed the Warriors in the first round of the playoffs. With a roster that still includes Lou Williams, Danilo Gallinari, Patrick Beverley, Montezl Harrell, Shai Gilgeous-Alexander, and Landry Shamet, Leonard could be the star that puts the Clippers over the top, with an infrastructure in place that is not unlike the Raptors'.

Meanwhile, things could swing the opposite way in the Eastern Conference. The Raptors, without Leonard, might be a borderline playoff team. That could open up an easier path for teams like the Bucks and 76ers. Teams like the Pacers or Celtics could be motivated to swing further deals to make a run at contending.

Kevin Durant's free agency was supposed to be a league-changing event. It may still be, but his torn Achilles tendon has put the effects of his move on pause until he returns.

Instead, it is Leonard, who has kept his free agency plans close to the chest all season long, who is now in a position to alter the league's balance of power. It is only fitting that while almost every other big free agent has made up his mind, the NBA world is still waiting on Leonard's decision.

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