Abstract 

This research examines the effect of mid-season absences on NBA players and how these affect their performance. We focus on the game logs of 19 players over the past 10 seasons who suffered injuries that led to absences of at least one month. The findings suggest that although there is a modest decline in metrics such as Points, Game Score, and Rebounds, this decline is statistically non-significant based on the sample studied.

Introduction 

Injuries and load management have become key topics in the NBA in recent years. Despite the Player Participation Policy which was introduced in 2023, the number of missed games by all players due to injury were up 13% in 2024-25. Several stars, including Joel Embiid, Kawhi Leonard, and Lonzo Ball, have seen their careers marked by injuries, often struggling to play more than 60-70 games in a season. Other players, though generally healthier, have occasionally missed weeks or months due to mid-season injuries. Has such an absence been a turning point in their performance?

This study explores whether mid-season injuries significantly impact player performance. By comparing key metrics before and after the injury, we assess whether players return to form or experience lasting decline.

Data & Methodology 

We extracted data from Basketball-Reference.com, focusing on game logs for 20 cases involving 19 different players who experienced an injury during the past 10 seasons. To be included, each case had to meet the following criteria:

• The injury was not season- or career-ending and did not occur during preseason.
• The player participated in at least 8 games both before and after the injury, averaging 20+ minutes per game.
• The injury led to an absence of at least 15 games or one month.
• The player was not traded during the season.

We calculated averages before and after the injury using both basic and advanced metrics. Absolute statistics (e.g., points, rebounds) were normalized per 36 minutes to account for playing time differences.

Results 

Pre- and Post-Injury Performance Comparison 

Figures 1 and 2 illustrate the average performance pre- and post-injury across five basic metrics (points, rebounds, assists, steals, turnovers) and several advanced metrics (TS%, Game Score, AST/TOV). The data reveals slight declines in scoring and efficiency metrics, while steals remain largely unaffected.

Scoring dips are likely linked to the type and location of the injuries. Hand injuries, particularly to the shooting hand, can reduce scoring efficiency. Lower-leg or foot injuries (e.g., ankle sprains) often prevent players from attacking the rim, instead forcing them into less efficient mid- or long-range shots.

Rebounding also sees a modest decline post-injury, potentially due to a decrease in physical readiness or caution in high-contact situations. Conversely, assists generally increase after a player returns. This is likely a result of decreased offensive aggression and an increased tendency to pass rather than shoot, especially when the player is still regaining confidence or fitness.

This trend is not reflected in the TS%, which remains nearly at the same levels post-injury. Meanwhile, the AST/TOV ratio improves, largely driven by increased assist numbers. Overall performance, as indicated by Game Score, also shows a slight but non-significant decline.

A paired t-test (see Table 1) was conducted to evaluate whether the observed changes in performance metrics are statistically significant by comparing each player’s average performance before and after the injury. While trends are visible, most differences fall within the margin of error for this sample size as the p-value indicates (<0.05).

Initial Return Phase: Performance in the First Five Games

We also analyzed the first five games after each player’s return, with the results being illustrated in Figures 3 and 4. Contrary to expectations, the data reveals a modest increase in performance across most metrics during this short-term phase. While this may seem surprising, several factors likely contribute to this pattern:

• Controlled reintegration: Players often return with minutes restriction and simplified roles, focusing on efficiency over volume during this period.
  
• Elevated focus and caution: A heightened sense of discipline and selective decision-making may lead to more efficient shot selection and fewer mistakes.
  
• Supportive matchups or rotations: Teams may ease players back by staggering their minutes against bench units or favorable opponents.
  

These factors may temporarily mask deeper recovery challenges. Although performance appears boosted initially, this may not reflect long-term trends or full physical readiness.

Notable Cases 

Mitchell Robinson 

The Knicks’ center had ankle surgery in December 2023, causing him to miss more than 30 games. Prior to the injury, Robinson had started all 21 games, anchoring the defense. However, after returning, he lost his starting role (played more than 20 minutes in only 3 out of 16 appearances) and struggled to regain his previous form.

Chet Holmgren 

Drafted second overall in 2022, Holmgren missed his rookie season due to a foot injury. He returned in 2023 with an impressive campaign, earning All-Rookie First Team honors. Early in the 2024-25 season, he averaged 2.6 blocks per game and was top-3 in Defensive Rating before suffering an Iliac Wing Fracture in November. After missing 10 weeks, Holmgren rejoined OKC’s rotation but his Game Score per 36 minutes fell from 20.3 to 16.5. He is still though one of the main reasons Oklahoma City reached the Western Conference finals.

De’Aaron Fox 

One of the most interesting cases is that of De’Aaron Fox. Fox had a good start during the 2019-20 campaign, averaging 18.2 points and 7 assists per game over 9 appearances till a Grade 3 Ankle Sprain in early November shut him down for 5 weeks. Remarkably, Fox returned in stronger form, scoring at least 15 points in most games and recording five 30-point outings. His Game Score per 36 minutes soared from 13.8 to 19 post-injury.

Conclusion 

Our analysis of mid-season injuries in NBA players yields two main conclusions:

1. Players generally do not seem to be widely affected and underperform in the first few games upon their return. Despite their limited playing time in some occasions, they still manage to put efficiency above volume.
2. Over the remainder of the season, metrics such as Rebounds and Steals per 36 minutes decline slightly, but these changes are not statistically significant in the sample examined.

These findings support the view that while injuries can temporarily impact performance, many players are able to return to near pre-injury levels over time, especially if they follow a strong rehabilitation program. That said, the effect varies case-by-case and may depend on factors such as injury type, recovery time, and the player’s physical profile.

Future research could examine a larger dataset or focus on specific variables, such as injury severity, player age, position, or historical durability. This would allow for more nuanced insights into how injuries shape NBA careers.