Recent rumours regarding the National Basketball Association (‘NBA’) adding two franchises in Las Vegas and Seattle have reignited discussions around league expansion, most notably when NBA superstar LeBron James expressed his interest in owning a Las Vegas team. Expansion has always been an attractive concept: new markets, more players, and creating new revenue sources that can elevate the league’s growth.
However, there are many barriers to successfully expanding the organisation. Financially, establishing a new franchise comes at a tall cost, with a reported buy-in price of $2.5 billion. For the game, expansion brings up concerns that the distribution of top talent amongst a larger number of teams would dilute the quality of NBA basketball, leading to a less appealing product for current and prospective fans.
The 2021-22 NBA season, plagued by the COVID-19 pandemic, saw a record number of players active at the NBA level. The league’s stringent health and safety protocols created unprecedented demand for temporary roster fill-ins, leading to unique instances such as when the Chicago Bulls scrambled to replace 10 missing roster spots due to COVID-19.
The data collected during this season is a useful yardstick to measure the impact that expansion, and the consequently larger player base, would have on the quality of basketball being played. The relationships between, one, margins of victory and the player base size, and two, a team’s success and the number of roster fill-ins they utilised, can highlight whether the pursuit of expansion can adversely impact the game’s quality.
Number of active NBA players and blowout victories
The average margin of victory calculates the average amount of points a team wins or loses by over the season. Higher averages generally signal a less exciting NBA product, as this suggests that ‘blowout’ victories (i.e., heavily one-sided victories) are occurring more frequently, and that a large skill disparity exists within the league. Since the league average margin of victory always equals zero, we will focus on the top 10 teams in this metric for each NBA season.
It is expected that the larger number of active players in the 2021-22 NBA season would cause the average margins of victory from the top 10 teams to be much higher than usual. This is because a larger active player pool would reasonably lead to more second-rate basketball players being called up to the league, which should increase the skill disparity between franchises and lead to larger average margins of victory. However, the data suggests otherwise.
The average margin of victory dropped in the 2021-22 season, indicating that teams were not winning, on average, by as much as in previous years.
Do more G-League call-ups lead to more losses?
Ideally, NBA teams would have their main roster playing all 82 games of the regular season to optimise their chances of success. Practically, this is an unattainable goal. The COVID-stricken 2021-22 season saw teams constantly needing to source additional players to ensure that they could field full rosters. The NBA’s ‘call-up’ system, where franchises can promote players from the developmental league (the ‘G-League’) to fill-in roster spots when needed, served as a solution to this issue.
Investigating whether a relationship exists between the number of call-ups a team made in the past season and their success can indicate whether players in the G-League are ready to compete at the NBA level. It is expected that the more players a team needed to call-up during the season, the fewer games they would win, as employing second-tier players should harm their ability to compete in the league. Again, the data suggests otherwise.
There appears to be a weak correlation between the number of call-ups a team made during the 2021-22 NBA season and the number of wins they achieved.
What does this all mean for the NBA?
Both sets of data strongly suggests that the NBA can expand its talent pool without significantly diluting the quality of basketball being played. But what are some other, unquantifiable considerations that the NBA should consider before expanding the league?
Expansion would mean more markets around the world would be able to identify with an NBA franchise, which can allow the league to expand its reach and sources of revenue. Recent decisions, such as adding a G-League franchise in Mexico and establishing the Basketball Africa League (BAL), indicate that the prospect of capturing new markets is being closely monitored by the NBA.
Further, an argument can be made that top G-League prospects are ready to compete at the NBA-level, but are being inhibited by the limited number of available roster spots. With the emergence of stars such as Pascal Siakam, Danny Green and Khris Middleton, all G-League alumni who went on to become key pieces in NBA championship teams, offering more developmental-calibre players NBA contracts is becoming an increasingly justified gamble.
Contrarily, the NBA should consider the value of limiting the league’s size to 30 franchises. Is the value of the league rooted in the scarcity of contracts offered? With revenues still suffering the knock-on effects of the pandemic, should the NBA hold off expanding to avoid the risk of further hurting its profitability?
Ultimately, there will likely never be an ideal time to expand the league. The true question is whether the league is willing to take the risk that that time is now.
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