(KTLA) – After a grueling 82-game regular season, the NBA postseason is only days away with 20 teams still in the hunt for a trip to the NBA Finals.

But before the playoffs can begin in earnest, a few things still need to happen: four teams need to get the boot and sent on summer break so the bottom half of each conference bracket can be finalized.

That’s where the NBA play-in tournament comes in.

If you haven’t been paying close attention to the NBA over the last several years, the Play-In Tournament probably feels like a foreign concept. For many basketball fans who watch the sport religiously, there’s still some confusion.

So, what is the play-in tournament and why does it exist?

The first time teams competed down to the wire for a last-second chance to make the postseason came in 2020 during a season shortened by the COVID-19 pandemic in which more than half of the league was sequestered at Walt Disney World in what has come to be known as the NBA Bubble.

The NBA brought 22 teams to Orlando, Florida in a last-ditch effort to save its season. Teams were given several tune-up games before the season resumed with an abbreviated schedule. But with only 16 teams making the postseason, the league needed to come up with a way to give those fringe playoff teams an opportunity to make a late season push that they would’ve gotten had the season not been suspended months earlier.

That format was significantly different than the current version and ended up resulting in only one game being played to determine final seeding for the playoffs. The Bubble season ultimately ended with LeBron James and the Los Angeles Lakers hoisting the Larry O’Brien Trophy in front of family, media members and league officials, as well as millions of fans watching from home.

The following season, the NBA approved the current format of the play-in tournament, which has remained ever since.

The tournament was devised by the NBA as a way to keep games competitive throughout the length of the entire season by giving teams in the middle of the pack a longer window to make a move and win a spot in the playoffs. By doing so, the tournament also provided the added benefit of discouraging some teams from punting half the season in order to improve their odds in the NBA Draft Lottery — a practice known as “tanking.”

With 20 teams in the hunt for the playoffs rather than 16, the NBA found that teams were taking the latter half of the season more seriously in hopes of bettering their standings and getting into the tournament — or avoiding it entirely.

So, how does the play-in tournament work?

The NBA is divided into two conferences, East and West, and the playoffs feature eight teams in each conference competing for a spot in the NBA Finals.

Each conference playoff bracket is seeded No. 1 through No. 8, determined by the team’s performance in the regular season.

Teams compete in a best-of-seven series and the winners advance to the next round to face the winner of one of the other series. Finally, the winners of both conferences will face one another in the championship.

Prior to the play-in tournament, the top eight teams in each conference received automatic berths in the conference playoffs.

But now, things are a bit different, with 10 teams staying alive even after the regular season concludes.

Each conference has its own Play-In Tournament that consists of the bottom four teams, seeds No. 7 through No. 10. Two teams will advance out of the tournament and secure a spot in the NBA Playoffs.

Rather than the top seed facing off against the bottom seed like most sports tournament formats, in the Play-In, the No. 7 seed (the highest seed) faces the No. 8 seed, and the No. 9 seed faces the No. 10 seed (the lowest seed).

The top half of the Play-In Tournament looks like this:

• #7 New Orleans Pelicans vs. #8 Los Angeles Lakers (Western Conference)
• #7 Philadelphia 76ers vs. #8 Miami Heat (Eastern Conference)

The winner of that game automatically wins the No. 7 seed in the NBA Playoffs for their respective conference.

The loser, meanwhile, is still alive, but has to play the winner of the bottom half of the tournament bracket, which looks like this:

• #9 Sacramento Kings vs. #10 Golden State Warriors (Western Conference)
• #9 Chicago Bulls vs. #10 Atlanta Hawks (Eastern Conference)

The loser of the No. 9 vs. No. 10 game is eliminated from playoff contention and can start planning their summer vacations.

The winner, however, goes on to face the loser of the previous series in a win-or-go-home game with the No. 8 seed up for grabs.

Once those games are completed and final seeds are determined, the NBA Playoffs can begin.

Although it might seem unfair for a team that finished in the top 8 to have to defend their spots against teams with fewer wins, the higher seeds still have distinct advantages.

In the 7 vs. 8 bracket, both teams only need to win one game to advance to the playoffs, either against each other or in the second Play-In Game.

Meanwhile, in the 9 vs. 10 bracket, a team looking to make it to the postseason would need to win both games they play to advance.

So, for example, if the Los Angeles Lakers want to secure their spot in the playoffs, they can finish as high as No. 7 by defeating the Pelicans. If they drop that game, they’ll still have a chance to make it as the No. 8 seed by winning their next game against either the Kings or Warriors.

For Stephen Curry and the Warriors, the best they can finish is the No. 8 seed and they’ll have to win two straight to make it a reality.

If it still seems a bit too confusing, just think of it in simplest of terms: winning = good/losing = bad.

Regardless of which teams survive the play-in tournament, they’ll have a tall task in trying to take down the top teams in their conference, all of which enjoyed an extra week of rest while the lower seeds were getting their houses in order.

Last year, the Miami Heat were more than up for the challenge.

After dropping the first game in the play-in tournament to win the No. 7 seed, the Heat snuck in after winning the second tournament game and were awarded the No. 8 seed in the Eastern Conference.

The Heat would then go on a historic run, dispatching the No. 1 seed Milwaukee Bucks in only five games in round 1 of the Eastern Conference Playoffs before eliminating the New York Knicks and Boston Celtics en route to the NBA Finals. They would later fall to Nikola Jokic and the Denver Nuggets in five games, but their unexpected run to the finals is the stuff of legend.

This year, the Heat have the opportunity to repeat that Cinderella performance, but they’ll need to worry about the play-in Tournament first.

The NBA play-in tournament begins Tuesday with the Lakers vs. Pelicans tipping off at 4:30 p.m.