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When Derrick Rose, the Chicago Bulls’ dervish of a point guard, went down in the 11th game this season, it was the 2012-2013 season all over again. Rose sat out that entire season recovering from a torn ACL and watched his team finish 45-37 and put up a fight against the Miami Heat in the second round of the playoffs. This season was supposed to be different — and now it wasn’t going to be at all.

Something else wasn’t different: The Bulls managed to finish above .500 without Rose yet again. That was for a whole host of reasons: the remarkable play of center Joakim Noah, the stellar coaching of Tom Thibodeau and an Eastern conference filled with chum, among others. But Chicago’s record this year also indicates that an injury — even of a star player — doesn’t always ruin a team’s regular season as much as we think it might. Sometimes the replacements are better than replacement level. And sometimes they just don’t swing that many games.

The Bulls’ record without Rose is just one anecdote, but this was a busy year for injuries in the NBA. Together, the league’s athletes missed more than 4,900 games to injury, the highest total since the 2008-09 season. Eighteen teams saw more games missed due to player injury than the prior season.

For the last two years, I’ve kept a database of every injury in the NBA — what the injury was, who suffered it, how many games he missed, etc. (Odd hobby, I know, but this is what happens when you’re an injury analyst.) The database includes every game missed since the 2008-09 season and includes more than 850 players. After watching such an entertaining yet injury-riddled season this year, I started wondering if that database could tell us whether and how the results would have changed if every player in the league had stayed healthy. Like, really healthy. So healthy that there wasn’t a single injury. Who makes the playoffs then?

To create this alternate universe, I put my database to work, simulating an entire season in which games missed because of injury were excluded.1 That meant approximating who took the place of the injured players, using injury listings and minute distributions2 to calculate a total number of minutes played for each player on a team’s roster. An important note: My method only tabulates when players play or don’t play; it doesn’t try to understand how a player’s value is affected if he’s playing through an injury.

Then, with FiveThirtyEight’s help, I assigned each player a talent rating using Daniel Myers’s ASPM, a box-score-based performance metric that does the best job of telling us how hypothetical universes play out.3 Once we weighted those talent ratings by the estimate of minutes played, we had a sense of how good each team would be with all of its players. From there, we simulated a whole new season using the 2013-14 NBA schedule, and compared the injury-free hypothetical reality to the actual season.

All that left us with what could have been, but almost certainly can never be. As you read the divisional breakdowns below, it’s important to remember that this alternate reality is not a glimpse into how a team would have improved or regressed if it never had to play a replacement player. Instead, it’s a holistic portrait of what would have happened to an entire league if no player missed time due to injury. You’ll see that some teams have worse records in the injury-free space (the New York Knicks, the Detroit Pistons, etc.), which might make you think their replacements were in fact better than their starters, even if the starters were healthy. But it’s really because in our alternate reality these teams don’t improve as much as other teams in the league, leading to more losses against full-strength opponents.

With all that preamble out of the way, here’s what an injury-free league looks like in each division, and in the overall playoff picture.

Eastern Conference

nba-playoffs-atlanticIt’s easier to make a surprising run to the top of your division when you’re the healthiest team in the league, as the Toronto Raptors were this season. If the Brooklyn Nets’ center Brook Lopez hadn’t fractured his right foot’s fifth metatarsal and forwards Kevin Garnett and Andrei Kirilenko hadn’t succumbed to back spasms that cost them a combined 45 games, the simulation predicts a healthy Nets team would have flirted with 50 wins. That increases their win total by four games, placing them first in the division. In real life, injuries overextended the minutes of veterans Garnett and Paul Pierce and increased the responsibilities of role players like Reggie Evans and Mirza Teletovic.

Not even a clean bill of health rescues the other teams in the division. The New York Knicks get worse in our alternate reality, not helped by their power forward Andrea Bargnani making up the 40 games he missed. Same for the Boston Celtics and their point guard Rajon Rondo. And the Philadelphia 76ers are hopeless no matter what: Rookie Nerlens Noel4 and shooting guard Jason Richardson, along with several other players, aren’t enough to keep them from finishing with the league’s second-worst record.

nba-playoffs-centralNot even a healthy Derrick Rose stops the Indiana Pacers’ march to the top of the Central Division. The Bulls’ worse record in our alternate universe doesn’t mean the Bulls would be worse with Rose, but more likely that the rest of the league gets even more of a full-strength bump than Chicago does, leading to 1.6 more losses for the Bulls.

The biggest drop in the division comes for the Detroit Pistons, who were the 11th-healthiest team in the league, with players missing 128 games overall. Despite their health, the Pistons still couldn’t win 30 games, and they fare even worse once the rest of the league is healthy, losing 3.5 more games in the simulation. The Milwaukee Bucks were the Eastern Conference team most handicapped by injury this season, with their players missing 318 games, but they gain only an extra 2.7 wins in the simulation. That suggests their roster was never that competitive to begin with. And Cleveland, despite adding 31 games from shooting guard C.J. Miles in the simulation, only records a slight uptick, winning a bit more than an extra game.

nba-playoffs-southeastThe Southeast remains the most competitive division in the Eastern Conference when injuries are excluded, but with an even denser grouping among its middle three teams. The team at the top of the division, the Miami Heat, distances itself thanks in part to a healthy Dwyane Wade. Wade’s 28 recovered games help net Miami 4.2 more wins, propelling the Heat to the top of the division and the conference.

The middle three teams — Washington, Atlanta, and Charlotte —  all clump together, with Atlanta winning an extra game thanks in part to a boost from the return of center Al Horford (53 games missed). Washington and Charlotte, meanwhile, dip. A never-absent Nene doesn’t help Washington much, since in reality the Wizards went 12-9 during the 21 games he wasn’t on the court. Charlotte was the team that most took advantage of an injury-filled NBA, finishing 5.8 wins above its record in the injury-free reality, so some regression to the mean is expected. And the Magic, well, the Magic aren’t notable in either reality.

Western Conference

nba-playoffs-southwestThe San Antonio Spurs remain the best team in the league, but with a franchise-record breaking 65.7 wins, 3.7 more than they actually had during the regular season. That’s what happens when you get an extra 44 combined games from Tony Parker, Kawhi Leonard and Danny Green.

Houston’s five-man starting unit finished ninth in most minutes played together this season, so it’s not surprising that the Rockets are unaffected by an injury-neutral schedule. The majority of Houston’s injuries occurred to bench players, and a few more games from backup center Omer Asik don’t move the needle.

Despite an additional 23 games from a healthy Marc Gasol, Memphis’s record drops a bit, with the Grizzlies losing 3.4 more games than they did in reality. Perhaps it’s because the teams they faced during Gasol’s absence were in poor health, including a James Harden-less Rockets squad, a Brooklyn team without Deron Williams, a New Orleans Pelicans team missing Anthony Davis and a Bulls team lacking Rose. Memphis’s play may improve with Gasol in the lineup (the Grizzlies went 10-13 while he was out) but so, too, do the rosters of the teams they face. That drops them below the Dallas Mavericks, who lose ground (2.2 games) but less of it than Memphis. At the bottom of the division, the New Orleans Pelicans gain the second-most games in the league (5.1), with the help of a full season from Anthony Davis, Ryan Anderson and Jrue Holiday, a trio that, in reality, played just 15 games together.

nba-playoffs-northwestAt the top of the Northwest Division, the Oklahoma City Thunder only get better, winning 3.6 more games with the help of a healthy Russell Westbrook, who missed 36 games this season. Those extra games help put more distance between the Thunder and the Portland Trail Blazers, who decline as the league gets healthier. Only Indiana’s starters played more minutes together this season than the Blazers’ starting five.

The majority of Minnesota’s injuries didn’t occur until the final weeks of the season and didn’t have a major impact on the Timberwolves’ overall finish. But the team directly behind them in the standings can use injuries as a legitimate excuse for failing to meet expectations. Denver lost more than 130 games to three separate ACL tears, including 82 games from starting small forward Danilo Gallinari. Combine those games with Javale McGee’s tibia fracture and it’s easy to see why the Nuggets finished as the NBA team most affected by injuries. They win 5.4 more games in our injury-free utopia.

The Utah Jazz are bad in all realities. The team ranked as one of the healthiest in the league, and it seems the Jazz likely picked up a few wins due to other teams’ injuries — wins that fall away in our simulation.

nba-playoffs-pacificThe Los Angeles Clippers remain the elite team in the Pacific and improve their record by two wins with an extra 20 games from Chris Paul. Two wins may seem like a small shift for the return of a player as good as Paul, but the Clippers played well without him (earning a .650 winning percentage), blunting the effects of his loss.

Like Portland, Golden State’s starting unit remained largely unscathed for most of the year, which knocks 2.4 wins off their total once the rest of the league becomes as healthy as they were. South 350 miles, the Los Angeles Lakers suffered through a nightmare season, losing player after player to injury with Kobe Bryant, Steve Nash, Pau Gasol (who combined to miss 165 games) and others sitting for significant stretches throughout the year. Yet removing these injuries doesn’t do much for the Lakers’ playoff push. It helps them pass Sacramento in the standings, but they only win 3.7 more games with all their players.

The real surprise is in Phoenix, not because the Suns’ record changes much (they gain only 0.1 wins), but because the rest of the league changes just enough that the Suns make the playoffs in an injury-free simulation. The Grizzlies are suddenly left out of the playoff picture, finishing .003 percentage points behind the Mavs for the eighth playoff spot.

The Suns are the only team to make the playoffs in the injury-free reality that didn’t in the actual season we just watched. Without injuries, playoff seedings change — it’s Miami, not Indiana that has home court advantage in the East — and as bad as the Eastern Conference was, it’s even worse once the whole league is at full strength. But all in all, very little is different.

nba-playoffs-all

For the endless talk about how injuries changed the game this season, if the entire league were healthy, the NBA would still look more or less like the NBA as we saw it. It’d just be a bit more entertaining.

Footnotes

  1. Games missed for personal reasons or suspensions were retained. ^
  2. I went through every team and tabulated each player’s starter minutes versus bench minutes, and how those minutes changed after injury, when I could. ^
  3. The FiveThirtyEight crew used an ASPM aging curve and came up with “talent” ratings for each player based on an age-adjusted weighted average of his performance this season and over the previous two seasons. ^
  4. In our simulation, rookies who never played were assigned league-average quality ratings. ^

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