Race car drivers understand death, more so than other professional athletes. Nearly every driver at the top levels has lost a friend or a rival in a race, an acquaintance from another series, a driver they grew up idolizing.

Death is a risk the drivers willingly take and their loved ones accept, knowing the passion for a profession that can kill.

Robert Wickens came to terms with the stakes long before he left a successful career in Europe racing touring cars to join the IndyCar Series. Was he thinking he could be seriously injured when he climbed into his car Sunday at Pocono Raceway? Most certainly not. Drivers don't become champions through fear.

Wickens certainly wasn't scared when the flag dropped and he went wheel-to-wheel as he tried to pass Ryan Hunter-Reay just a few minutes into the race. The cars hurtled through the turn, each driver mashing the gas, refusing to give an inch of asphalt in a breathtaking game of chicken. Those moments are so beautiful and the very essence of auto racing.

But those moments can change from thrilling to terrifying once wheels connect on a pair of open-cockpit Indy cars. Open wheel's history is filled with instances of cars sailing into fences, spinning like tops through the air and leaving parts scattered over the track with drivers often lucky to come away alive.

Wickens and Hunter-Reay touched their cars ever so slightly — this was no beating and banging like NASCAR — and the racing suddenly turned ugly. Hunter-Reay's car spun into Wickens' path and Wickens launched over it and into the fence. His car spun over and over, smacking along the fence, and it appeared to smash into a pole as it partially disintegrated into a minefield of debris. As the car was spit back toward the track, the in-car camera from Hunter-Reay's seat showed it missed clipping Hunter-Reay's head by inches.

Wickens was airlifted to a hospital in nearby Allentown, Pennsylvania. IndyCar said Monday the 29-year-old Canadian will undergo surgery for a spinal injury. He suffered injuries to his lower extremities, right arm and spine and a pulmonary contusion.

Both he and Hunter-Reay are lucky to be alive. The outcomes could have been worse — if Wickens' car went into the fence cockpit first, if the protective tub had not remained intact, if the debris field had been fractions of an inch lower as it sailed over Hunter-Reay's head.

Enough ifs to ignite a renewed safety debate, calls for different fencing at ovals or halos over the cockpits to protect drivers' heads.

Everything should be looked at because improving safety should always be a priority. But racing is never going to be 100 per cent safe. If risk was not part of the show, there would be no show.

It took two hours to repair the gaping hole in the Pocono fence and the IndyCar drivers, a close-knit group , could do nothing but wait for an update on Wickens while waiting for the race to resume.

Alexander Rossi, who went on to win , was asked about that balance during the delay.

"You compartmentalize," he said.

Michael Andretti was accused of being insensitive when he was interviewed after the accident. The team owner said Wickens should have let off the gas and it was too early in the race to be so aggressive, prompting criticism on social media over his perceived detachment.

Perhaps he was just compartmentalizing. Andretti has lost enough friends to racing accidents — including Dan Wheldon in 2011 and Justin Wilson, who was driving an Andretti car in a 2015 accident at Pocono — to understand the emotions enveloping the paddock on Sunday.

Sebastien Bourdais, involved in his own bone-breaking accident last season at Indianapolis, was clearly shaken during the delay. He drove through large pieces of debris, saw Wickens' car in the fence and had to process it all while not forgetting the race was going to resume.

"I was really worried for him ... he's hurt, but I hope not too bad. He's alive," Bourdais said.

As for getting back in his car?

"It's what we do," he said matter-of-factly. "It's a bit easier if you know the guy's made it."

That's about as raw as it gets for a race car driver because they don't talk about risks or admit fear. A scared driver won't win many races. So the risks remain tucked away while everyone knows there is no such thing as safe.

Safer? Sure. Safe? Never.

IndyCar will probably adopt the halo over the cockpit, but only when the head protection device has been effectively tested and is ready. Since Wheldon died when his head hit a pole in the fence at Las Vegas, the drivers have made a compelling case for fortified fencing and alterations that would move the poles outside the track. That should get a strong second look.

For now, they race.

When IndyCar called drivers back to their cars Sunday, Bourdais was unhappy with the way the fence had been repaired. He made it known he felt the job was inadequate and a danger to the competitors.

Then he got back in the car.

"I'm old but I'm not wiser," he said. "Everybody's in the seat. You gotta go."

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