After 133 of 200 laps were completed (332+1⁄2 mi (535.1 km)), rain halted the race, and Gordon Johncock was declared the winner, the first of his two Indy triumphs (1973, 1982).

Competitors, media, and fans were eagerly anticipating the possibility of breaking the elusive and daunting 200 mph (321.9 km/h) barrier during time trials.

The race was scheduled for Monday May 28, but was aborted by a red flag because of a major accident collecting multiple cars at the start.

Driver David "Salt" Walther was critically injured and numerous spectators in the track boxes and first few rows of the Paddock grandstands suffered burns from a fireball resulting from the accident.

[8] Only a fraction of the typical Indy crowd arrived to watch the race by the time it was run on Wednesday May 30; and in fact since schools were closed in Speedway and within a few miles around west Indianapolis due to traffic, many hundreds of schoolkids and parents were bused in to fill the grandstands for free.

Owing to the tragic circumstances, relentless weather problems, rain-shortened finish, and overall glum mood during the month, the 1973 race is widely considered the worst year for the running of the Indianapolis 500.

[13] National media opinions, as well as those from team owners and crew, were highly critical in the aftermath of the race, focusing mainly on inadequate safety measures.

[19] * Includes days where trackactivity was significantlylimited due to rain Just one year prior, USAC began allowing bolt-on wings.

In addition, engine development with the turbocharged version of the venerable I-4 Offenhauser had resulted in horsepower readings in high-boost qualifying trim in excess of 1,100 hp (820 kW).

In the final ten minutes, two cars (Tom Bigelow and Sammy Sessions) made it out on the track for qualifying attempts, but neither were successful.

Rather than withdraw (and forfeit their starting spot to Tom Bigelow, the first alternate), the crew kept the engine issue secret, and gridded the car as normal.

As the green flag fell, Steve Krisiloff's car developed ignition problems and slowed on the front straightaway, falling back to parallel with the fifth row by the time he crossed the start/finish line.

[26] The impact ripped open both of Walther's fuel tanks, sending 75 gallons of flaming methanol in a massive pale blue fireball (not apparent on TV or film footage) and dousing many spectators, with the blast of heat felt at least 100 yards away in the Paddock grandstand and Track Boxes, per eyewitness accounts.

The car landed back on the racing surface upside-down, and spun wildly down the main stretch, spraying burning fuel in all directions.

Safety crews attended to the crash scene, aided injured spectators, and also started repairing the catch fence and stanchions.

A heated pre-race meeting was held between the drivers and officials, and the subject of the crash and the speed of the pace car at the start was the focus.

The health department overseeing the event even threatened to keep the race from running at all if it was rained out again on Wednesday, due to the deteriorating conditions of the infield.

[32] Around midday, the sun finally came out for a few hours, and the track surface dried enough for a race start at 2:10 p.m. On the pace lap, the car of David Hobbs began smoking heavily.

Savage came to rest adjacent to the outer retaining wall, fully conscious and completely exposed while he sat in a pool of flaming methanol fuel.

Among those who did was George Bignotti, chief mechanic for Gordon Johncock, and 22-year-old Armando Teran, pit board man for Graham McRae.

Teran suffered crushed ribs and a broken skull, and although he lived through the initial impact, he died shortly afterward after being transported to Methodist Hospital.

Al Unser's day ended with a blown engine on lap 75, and Gordon Johncock, another of Savage's Patrick Racing/STP teammates, assumed the lead.

Track officials began assembling victory lane, as dark skies were looming, evening was soon approaching, and they did not expect the race to go the full distance.

Vukovich refused to come down until her husband had been confirmed the winner, during which it was discovered that scoring had briefly been interrupted after someone accidentally kicked out a power cable.

Johncock and Patrick, and a few other crew members ended the day with a "victory dinner" which consisted of fast food hamburgers at the Burger Chef just east of the Speedway on Georgetown Road.

Dr. Steve Olvey, Savage's attending physician (and later CART's director of medical affairs), claimed in his book Rapid Response that the real cause of death was complications related to contaminated plasma.

[citation needed] According to Savage's father, the percentage of oxygen they were giving Swede just prior to his death, due to the damage to his lungs from the flames inhaled from the accident, was such that there was no way he could have survived, even if he had not contracted hepatitis B.

The angled inside wall at the northwest corner of the track (which had also played a role in the Dave MacDonald/Eddie Sachs double-fatality in 1964) was removed, and the pit entrance was widened.

Analyst Jackie Stewart was to be the color commentator, but was only able to be at the grounds on Monday and Tuesday as he left the Speedway Wednesday for Formula One commitments at the 1973 Monaco Grand Prix which he won.

The broadcast was slightly edited from the original airing, as a scene in the immediate aftermath of Armando Teran's fatal accident was omitted (but is still available on YouTube).