Juan Pablo Montoya spent just two years on the American single-seater scene first time around, but that was long enough to create a legend.
The speed and style with which he mastered the CART World Series, oval racing and even the toughest speedway of them all at Indianapolis left his United States rivals convinced that the Colombian would go on to be an all-time great in Formula 1.
It didn't quite work out that way, and perhaps Montoya's aggression and temperament were always better suited to the rougher-round-the-edges nature, atmosphere and venues of US racing.
Following the shock news that Penske had completed a deal to bring the Colombian back to single-seaters, AUTOSPORT picks the 10 key moments from when Montoya took the US by storm in 1999-2000.
April 10 1999: Motegi
Putting a member of a great American racing dynasty in the wall at high-speed in a practice session and triggering a shoving match between two legendary team bosses was not the ideal way to make a first impression. Making up for it two days later by nearly winning your second oval race was admirable atonement.
In his haste to get past 1991 champion Michael Andretti in practice for round two at Motegi in Japan, Montoya put both his Chip Ganassi Racing Reynard-Honda and Andretti's Newman/Haas Swift in the wall.
A stunned Andretti was expecting something more contrite than the nonchalant rookie who laughed the shunt off as they shared an ambulance back to the paddock.
His team boss Carl Haas was similarly enraged and headed to Montoya's pit for some spleen venting, only to be physically fended off by Chip Ganassi in a tussle that sent Haas's trademark cigar flying.
Was Montoya, who copped a $5000 fine, ruffled by all this? Hardly. In the race he scorched through the field from 15th on the grid to join Andretti's and Adrian Fernandez's lead battle.
Just as he was poised to pass Fernandez, Montoya's car ran out of fuel, leaving him four laps down in 13th. But that hardly mattered. In the space of one weekend in Japan, the CART contenders had learned a lot about their newcomer...
Andretti on the shunt: "I'm not sure which disappoints me more, the move he pulled or the way he handled the situation afterward. I hope he changes his attitude."
April 18 1999: Long Beach
After that oval performance, Montoya's first CART street race was eagerly awaited. After all, he had lapped the Formula 3000 field in Pau, so legendary Long Beach was unlikely to faze him.
But what was most impressive about the maiden win Montoya duly pulled off was the relative lack of fireworks.
He qualified a quiet fifth, slipped past Max Papis ("he wasn't that difficult"), Bryan Herta ("he was the hardest guy") and Dario Franchitti, and then picked up first place when Tony Kanaan crashed out of the lead.
Montoya then left the series' established road-course benchmarks Franchitti and Herta in his wake as he reeled off win number one in start number three.
"We did quite a good job..." was his summary.
May 2 1999: Nazareth
It was back to the ovals after Long Beach, and this year the tricky 0.9 miles of Nazareth were made tougher still by a new wing package that series veterans predicted would cause plenty of crashes and preclude passing.
Montoya wasn't fussed. He claimed his first series pole, led the majority of the race, proved passing WAS do-able in a three-abreast battle with Helio Castroneves and PJ Jones, and emerged victorious, taking the points lead in the process.
It was sophomore Castroneves who stuttered under pressure, stalling in the pits, spinning and then crashing more permanently as he tried to stop his fellow young gun (and 2014 team-mate) stealing the headlines again.
May 15 1999: Rio
Montoya arrived in Brazil trying to calm expectations after his astounding April. He said he'd be happy with a few points, and qualified back on row two this time. The Ganassi team said it would make a cautious start and see how the race unfolded...
...but by Turn 1, lap one, Montoya was in the lead, having sliced past Christian Fittipaldi and Franchitti in a single move. He then used the fearless cold-tyre pace that had swiftly become his oval trademark to pull away and leave their battle in his wake.
A third straight victory was a record for a rookie, and gave him an early 15-point series lead.
July 11 1999: Road America
That hat-trick set Montoya on course for the title. It wasn't all plain sailing, and several mishaps - some mechanical, some self-induced - punctuating his eventual tally of seven wins meant he ended the season equal on points with Franchitti, winning the crown on a tie-break.
Along the way, one of his most impressive races was one that went awry: Road America.
Montoya didn't take pole at CART's finest venue, but felt the 0.139s he lost to Andretti and more had been squandered when he messed up the Carousel on his best lap.
He made amends by storming around the outside of Andretti at the first corner, only for a midfield tangle to cause a red flag. The stunned Andretti vowed he wouldn't let that happen again, but Montoya wasn't listening, and pulled off an identical move. Then he pulled out a two-second lead on lap one alone. By lap six he was 6.1s clear.
Only his gearbox could stop a certain Montoya victory. Third gear broke, costing Montoya a few seconds as he figured out how to work around its absence, having a quick spin without losing the lead along the way as he changed down from fourth to second too hastily. But having adapted his style, he continued to maintain a five-second lead.
Soon the gearbox was so sickly that it would only change gear in any direction while accelerating out of corners. Still Montoya's lead stayed comfortable. It was only when the dying car ground to a halt with six laps to go that victory finally got away.
Montoya after retiring: "The car was brilliant. Without that we'd have beaten them by ages."
September 5 1999: Vancouver
American single-seater races in the wet are invariably chaotic given their rarity. It was only the incessant yellows in a sodden Vancouver race in 1999 that stopped Montoya's win being his most dominant of the year.
Every time he did get some green-flag running, Montoya was able to pull out up to three seconds per lap over his rivals.
And he was doing it in a measured way, as proven by his rivals' misadventures. Both Paul Tracy and Franchitti managed to pass Montoya for the lead at different points, but overstretched themselves in the process and crashed.
Even as the track dried late on, Montoya was able to nurse his wets to perfection and rattle off another win.
May 14 2000: Motegi
Ganassi's shock switch to Lola chassis and Toyota power over the winter prevented a repeat title for Montoya as his second and final CART year was spent enduring the teething troubles of what would eventually prove a strong package... by the time he was in F1.
Time and time again Montoya would lead races only for a mechanical failure of some sort to halt him. It would be one of the most hotly contested title fights in CART history, but the fastest man of the season barely featured in the points battle.
Motegi typified his year. Having taken pole, Montoya stormed away from the field with ease. Only team-mate Jimmy Vasser was in the same class, and Toyota was soon savouring the prospect of taking its maiden series win in its home country and at a track owned by arch-rival Honda. The biggest question was how few drivers would be left on the lead lap.
Then at his final pitstop with 37 laps to go, somehow a pneumatic airline wrapped around an electrical lead to the turbocharger's pop-off valve, ripping the valve open as Montoya accelerated away and strangling the engine. He had to limp back for it to be reset and could only salvage seventh.
Montoya: "I had such a great car today. It was so fast. It was just awesome!"
May 28 2000: Indianapolis
It turned out to be the race that started the CART teams' drift towards the Indy Racing League, a tipping point that would ultimately end the US single-seater war with victory for Tony George's series.
At the time, though, it seemed like a crushing triumph for CART, as its talisman popped up to the championship's rival and blitzed the field in the biggest race of them all.
IRL convert Al Unser Jr was among the sceptical voices who warned that Indianapolis would bite the over-aggressive Colombian.
But it was the IRL regulars who were doing the crashing as they tried in vain to keep up with Montoya. Poleman Greg Ray gave it the best shot until he hit the wall, and 1996 winner Buddy Lazier did his utmost in a strong final stint, but fell short as Montoya led 167 of 200 laps and became the first rookie Indy 500 winner since Graham Hill on a seismic day in American single-seater racing's history.
June 5 2000: Milwaukee
Just a week later, Montoya finally managed his first CART win of the year. It had all the hallmarks of what was now a classic Montoya drive: stunning cold-tyre pace to break his rivals, yet achieved without compromising fuel economy, adding to the advantage his car control gave him on fresh rubber straight after pitstops.
It was something of a false dawn, though. The Lola-Toyota package's problems had paused, not vanished, and it would be two months before he won again. Plus the relative publicity disparity between Montoya's Milwaukee victory over a much stronger field and his Indianapolis cruise intensified the alarm bells ringing among teams, manufacturers and sponsors...
July 23 2000: Michigan
It was entirely appropriate that what many regard as CART's greatest-ever race featured Montoya in a starring - and victorious - role. And equally appropriate that Andretti was his sparring partner.
A year earlier, Andretti had denied Montoya a Michigan win by just 0.032s as Papis ran dry in front of them. Into the final laps of a typical 'Handford wing' race, featuring incessant slipstreaming and passing, Montoya and Andretti had broken clear in a class of their own.
The statistics showed eight passes for the lead in the last 20 laps, but that only counted those taking place at the start/finish line. The reality was at least double.
On the final lap they came up behind backmarker Tarso Marques at the final corner. The two cars were brushing wheels at well over 200mph as Montoya used Marques's draft to get a slight edge and squeezed himself into a narrowing gap between Andretti and the wall. His margin of victory was just 0.04s.
"It's fun racing with guys you can trust," said Montoya of Andretti. Motegi 1999's wall-bashing, cigar-flying spat seemed a very long time ago...
Montoya on the final battle: "Michael was pushing me in the last corner and I could see Tarso moving up.
"I wasn't going to lift; if I had to, I was going to bump him and give him a little push. Fortunately, he gave me a little bit of a tow and I thought phew, that was close.
"I lost by the same amount last year, so I'm happy to win this one."