OAKLAND, Calif. -- When Steve Kerr decided it was time to rest four players in mid-March, his team had already won 51 games and was cruising to the best record in the Western Conference by a landslide.
Still, the complaints rolled in – angry emails and tweets directed at Kerr from fans who'd paid good money to see the NBA's best team and its All-Star backcourt of Stephen Curry and Klay Thompson.
“It was somewhat controversial,” Kerr deadpanned last week while preparing his team for a trip to the NBA Finals.
Just a sample of the Twitter backlash directed at Kerr: “Nothing like spending $250 on tickets for my son's 7th birthday only for you to bench his favorite player. Thanks Steve.”
Ouch. And that wasn't all. Thompson's family had bought a huge block of tickets for the game in Denver on March 13, only to see him benched along with Curry, Andrew Bogut and Andre Iguodala. The Warriors lost 114-103, but won in the long run.
Here's how.
Kerr didn't draw names from a hat or use a coach's intuition in deciding his key players needed a break. He used information gathered from wearable technology, the next frontier in the NBA's rapidly accelerating analytics movement.
On the heels of a six-game, nine-day road trip, players were reporting that they were starting to feel worn down. Golden State's director of athletic performance, Keke Lyles, has players fill out a questionnaire every morning to measure soreness, fatigue, sleep quality and other factors that are so important to recovery and injury prevention.
In addition to the red flags on the players' questionnaires, the data Lyles had been collecting all season – using the NBA's SportVu cameras in games and wearable technology from Catapult Sports in practice – confirmed his fears.
“We felt like all those guys were reaching their limits,” Lyles said.
With player movement captured at 25 frames per second during games with SportVu cameras, teams can monitor players' movement intensity and acceleration – and spot drop-offs that might indicate fatigue and overuse. Layering that in-game data with metrics from a biomechanical movement device that the players wear in practice, Lyles reported to Kerr that it was time to take action.
“A lot of non-contact injuries are fatigue-related,” Lyles said. “If we see big drops consistently over the last few games, and we know in practice they've dropped and they're telling us they're tired and sore and beat up, then we start painting a big picture: ‘Yeah, these guys are probably fatigued.' When they're fatigued, they're at a higher risk.”
Kerr, ringleader of the most entertaining basketball show on Earth this season, didn't take the decision lightly. He even emailed fans to explain the reasons behind his decision.
“We don't like the idea of sitting someone out because fans pay,” assistant general manager Kirk Lacob said. “We get it. But we did agree that if we got to this point, we would sit them out.”
“This point” was a place where the Warriors – especially stars Curry and Thompson – arrived after the All-Star break. Lyles and the training staff had developed pre-set parameters for what they considered to be a danger zone; a combination of the player feeling fatigued and proof of diminished load capacity in the SportVu and Catapult data.
“We found that we had multiple guys red-lining,” Lacob said. “It was an easy decision. … Steve actually said, if one of those guys got hurt and he hadn't sat them out knowing that information, he could never forgive himself.”