The pre-race festivities continued, the engines were fired, the cars left the grid, and the 99th Running of the Indianapolis 500 was underway.
Green-flag racing did not last very long, though; Takuma Sato ran out of room on the outside of the exit of Turn 1 and was made side-by-side-contact with by 20-year-old Sage Karam. Ryan Briscoe, replacing the injured James Hinchcliffe in the No. 5 Schmidt Peterson Motorsports car, was also involved in this accident.
The restart following this incident was originally aborted due to damage to Juan Pablo Montoya's car; he was hit from behind by Simona de Silvestro during the yellow. Eventually, the rear wheel guard of his No. 2 Verizon Team Penske Chevrolet broke off from the car, extending the caution period and allowing more time for a rear wing replacement for the Colombian.
The first lap of green flag racing was completed finally on lap 13 of 200. Dixon led the field to the green, and no passing in the top three positions took place until Kanaan took second from Simon Pagenaud. He then began to pressure polesitter Scott Dixon for the lead of the race and finally took it over on lap 19. Just two laps later, though, Dixon darted back by his teammate, regaining the lead.
This back-and-forth battle for the lead of the race between the two Ganassi teammates continued; Kanaan proved he had a great car as he went back through to the lead on the 22nd lap, shooting by Dixon into Turn 3.
At this early stage in the race, two Ganassi cars and three Penske cars occupied the top five.
On lap 34, with Dixon out front, Penske's Simon Pagenaud began to inititate a battle with Kanaan for second position. This was just before the first round of pit stops; Dixon came in on lap 36, then in came Kanaan on the following lap and Pagenaud as well.
One-fourth into the race, Dixon was being pressured by Simon Pagenaud. Kanaan then went through on the No. 22 Penske car of Frenchman Pagenaud, but Pagenaud got him back on lap 54.
At this stage, Scott Dixon, Tony Kanaan, Simon Pagenaud, Helio Castroneves, and Will Power made up the top five.
Less than 10 laps later, Bryan Clauson found himself in the Turn 4 wall, bringing out the second full course caution of the race. Clauson was giving room on the inside to faster cars, but a lack of grip on the higher line of the track saw him head straight into the wall - and his race was over. The "usual suspects" of the race of Pagenaud, Dixon, Kanaan, Power, and Castroneves were the top five as Clauson's car made its way back to the pits.
The restart came on lap 70 of 200 and saw Pagenaud lose the lead to Scott Dixon - for a short while though; on lap 72, Pagenaud found himself back in the lead of the race.
On the following lap, though, Kanaan went from third to first in Turn 1, taking a commanding lead of the '500'. The lap after that, the 74th, saw Dixon go back to the lead into Turn 1. Two laps later, Kanaan was back in the lead. This incredible and non-stop changing of the lead was perhaps the product of the new aero kits.
At the halfway point of the race, Castroneves took over the lead during a cycle of pit stops. On lap 107, seven laps into the second half of the 500 mile race, Pagenaud had the lead of the race in his possession with Kanaan, Montoya, Power, and Dixon completing the top five behind him.
The next accident of the race came on lap 114 of 200. Ed Carpenter was attempting to make a move on Oriol Servia into Turn 1, and he made contact with the left rear wheel of Servia, sending them both into the wall and ending their races.
During the pit stops that took place under this caution period, a member of the crew of the No. 18 car was injured as the other Dale Coyne Racing car made contact with Pippa Mann, sending the No. 19 DCR car into the front right wheel-area of the No. 18. The member was taken to IU Methodist Hospital.
The restart following this accident of the reigning two-time polesitter of Ed Carpenter and Oriol Servia came on lap 123.
Will Power went to the lead by teammate Simon Pagenaud into Turn 3, but was passed for the lead of the race three laps later by Scott Dixon. Kanaan ran fourth after being sixth at the restart after losing position during his pit stop under the caution.
The first notice that Colombian Juan Pablo Montoya could win the race came on lap 130 when he was up to second position after being last on track in the opening laps of the race. His obvious speed that saw him advance through the field to this point showed that he would likely contend for the win as the checkers drew near.
His teammate Simon Pagenaud took second from him, but Montoya kept him and Scott Dixon in his sights as he sat in third.
By lap 142, Scott Dixon had led 70 laps of the race, adding to the number of laps in his career that he has led in the Indianapolis 500 - and moving up to 12th on the all-time list of laps led at the '500'.
Scott Dixon continued to lead until surrendering the lead to Simon Pagenaud when he came in for a pit stop. Two laps later, Pagenaud came in as did his Penske stablemates in Montoya and Power. As these three were exiting pit lane, they were almost three-wide and nearly made contact before rejoining the track.
Just one lap after these three rejoined the race (lap 154), hectic racing was going on throughout the field - before Tony Kanaan made heavy contact with the wall. At just past the halfway point, this was the third caution of the race. Note that the 98th Running last May was green until 140 laps (just under halfway) in.
The restart came on lap 159 of 200. Charlie Kimball led the field to Turn 1 but was passed by Scott Dixon on the very same lap. At lap 167, the top five was made up of Dixon, Power, Montoya, Pagenaud, and Marco Andretti. Three laps later, the yellow came out for debris on the track. The race was again restarted on lap 173 with Justin Wilson leading the field to Turn 1 with Carlos Munoz just behind him - two Honda-powered cars at the front of the race.
Four laps later came the most heavy crash of the race. Jack Hawksworth made contact with the rear of Sebastian Saavedra's car, spinning them both as they headed into the Turn 4 wall. Stefano Coletti then made a massive impact into Saavedra's No. 8 Ganassi Chevrolet as the Colombian slid from the outside wall to the inside wall - which he also made contact with. Saavedra's boot had to be cut for him to be taken out of the car; he was then carried to the ambulance and clean-up continued of the large amount of debris that scattered the track on the exit of Turn 4.
The race was restarted with 15 laps to go; Will Power led the field to the green flag.
With just seven laps to go, equal distance separated the top three cars of Will Power, Scott Dixon, and Juan Pablo Montoya, as Charlie Kimball ran fourth, ready to pick up the pieces if necessary. As this battle continued in the latest stages of the race, it became more and more evident that any one of those top cars could have won the race.
The final pass of the race and the pass for the win came with three laps to go. Montoya passed his Penske teammate and Angie's List Grand Prix of Indianapolis winner Will Power with Scott Dixon suddenly dropping to fourth behind Kimball.
Power's shot at winning the race did not go away until the final turn of the final lap when Montoya raced toward the yard of bricks - and won the Indianapolis 500 Mile Race for the second time of his career.
Behind him, the final podium was rounded out by Will Power and Charlie Kimball.
Following the epic battle to the checkers, Montoya had the wreath placed upon his shoulders as he passed the milk to his family, sharing a bit of the victory.
The next round of the 2015 Verizon IndyCar Series will be on Belle Isle in Detroit, Michigan. Next weekend will feature not one, but two IndyCar races, one each on Saturday and Sunday, as the lone doubleheader weekend of the 2015 season. Juan Pablo Montoya, who had the points lead before today's race, will head to Detroit - the home city of Roger Penske and Team Penske - with a large lead in the drivers' championship.
The 99th Running of the Indianapolis 500 Mile Race was as exciting as those that have come before it.
Aaron Durant is the editor of the VAVEL USA Racing section. Follow him on Twitter at @DoubleA291. Be sure to follow the brand-new Twitter account of IndyCar coverage on VAVEL USA, @VAVELIndyCar.