NBA Mythbusting: Are Coaches Resting Their Players More This Year?

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The Myth: Coaches are resting their starters more often this year.

With the compressed schedule forced upon coaches and players by the lockout, rest for a team’s key players is at a premium and is more important than ever. As a result, the popular perception seems to be that coaches are resting their top players more often – the whole league, supposedly, is pulling a Popovich. Blowing out a team? Rest your starters. Getting blown out? Put the bench in. Plan on sitting your most important player for a 4-minute stretch to end the first quarter? See if you can stretch that to include the first two minutes of the second.

The Test: What percentage of a team’s total minutes are being played by the six most active players on each team?

In order to see if that’s actually the case, I figured out what percentage of total minutes are being played by the top six in minutes played for each team. The rationale behind stretching it to six players and not just five was to include teams like Oklahoma City, which brings one of their most important players off the bench, and to help account for early-season injuries that might have shifted a backup into a starting role for several games this season.

The Data*:

*Data for the 2011-12 season is through games completed on 2/12. 

The “Percentage Difference” is calculated not as a simple subtraction of this year’s percentage minus last year’s; instead, it’s this year divided by last year, minus 100%. Atlanta, for example, gave 69.64% of its total minutes to its six most active players last year, vs. 66.86% this year. That means they’re 96.01% as top-heavy this year – or a decrease of 3.99%, expressed as -3.99%.

Well, well, well. It looks like the data doesn’t back up the myth; teams are actually 2.84% more top-heavy this year than they were last year. Only nine teams have seen a decrease in the number of minutes played by their top six this season. The three teams to see the largest decrease in their percentage were the Mavericks, Warriors and Hornets, three teams that have been hit hard by injury and roster shuffling.

The Pacers, Cavaliers and Wizards saw the greatest increase in playing time for their top six. Indiana has “benefited” from the addition of David West, the ascension of Paul George and an increased workload for Tyler Hansbrough; having players on which they can rely is likely a large part of the Pacers’ improvement this season. The heavier playing time for the starters in Cleveland is predicated on being able to lean on Kyrie Irving and a – until now – healthy Anderson Varejao being in the lineup regularly. The Wizards, too, have improved health (and no trades, yet) to thank for their increase. Last year, the six players who saw the most playing time for Washington averaged 64.5 games in a Wizards uniform out of a possible 82; this season, the top six averages 27.1 games out of Washington’s 28 so far.

Speaking of trades, some might wonder how large of a factor the trade deadline is; surely some teams’ totals last year were affected drastically by the midseason departure of a player who otherwise would have been in the top six. The Carmelo Anthony (Denver and New York), Marcin Gortat (Orlando and Phoenix) and Deron Williams (Utah and New Jersey) trades, in particular, affected the balance of minutes played for those six teams.

However, if we adjust those teams’ totals and assume those trades never happened, the league would still be 1.9% more top-heavy this year.

The Conclusion: Inconclusive, but leaning toward Busted.

As the season progresses and the trade deadline passes, it’s perfectly reasonable to anticipate this year’s rate regressing to last year’s. However, the takeaway here is that, at the very least, coaches are not resting their starters/top six players any more than they did last year. Be it due to injury or the night-in, night-out pressure to win and stay off the hot seat, the distribution of minutes so far this season is actually more compact than last year. When your favorite Blazers or Bulls fan complains about their coach not pulling the starters in a blowout, they’re not just blowing smoke. It’s a league-wide trend.