It’s difficult to think of two countries with less climatic, cultural and economic crossover than mañana Mexico and like-clockwork Switzerland.

They’re chilli peppers and Emmental.

But Pedro and Jo – Rodríguez and ‘Seppi’ Siffert; Gulf Racing Porsches and Yardley BRMs – found plenty of common ground. Often fighting over the same piece of Tarmac, theirs was an iconic rivalry aboard iconic machinery.

I am well aware that it is possible to read too much into a photograph. I know, for instance, that there was 999km to go at Spa in 1970 when that shutter clicked. But there is no doubt in my mind that those few thou encapsulated it.

All.

It bears witness to a moment of terrifying commitment that causes you to gasp and then to smile and finally to chuckle.

The gasp is elicited by the trading of paint at the entry to Eau Rouge. The smile lies in the knowledge that both drivers were cut from the same competitive cloth: colourful, with a ragged edge. The laugh is triggered by the gap. The knowing, healthy distance that the other Porsche 917s, plus the works and privateer Ferrari 512Ss, have allowed between themselves and that couple of red-mist crazies in the blue-and-orange cars ahead.

Trouble in the Ardennes damp was clearly expected. But Pedro and Jo made it – though it would be a stretch to say safely – through. The former went on to set the fastest lap that day – more than 20 seconds quicker than the previous year’s best. But it was the latter, thanks to sterling support from co-driver Brian Redman, who won for a JW Automotive team that no doubt gasped, smiled and chuckled – apart perhaps from boss John ‘Death Ray’ Wyer, for whom winning was a very serious matter indeed.

That win was a very serious matter for Jo, too. Porsche was his patch – he’d won five times for it in 1969 (with yeoman Redman) – but already newcomer Pedro had torn him off a couple of strips by winning first time out in a 917 at Daytona – Siffert never would finish a 24-hour race for Porsche – and then in sensational style at a sodden Brands Hatch.

Blue collar Siffert had worked too hard, wheeled-and-dealed too relentlessly, to get where he was to give it up without a fight. Like all ex-bike racers, he looked balsawood frail but was as tough as teak.

But privileged Rodríguez had raced bikes too. And like Siffert, he had driven the wheels off anything and everything he could sit his bum in. And again like Siffert, it would be a long time before Formula 1 fully appreciated his talents.

Having raced throughout the 1960s their rivalry came to a head in 1971 when they were paired at BRM as well as at JWA.

Boots were on different feet now. BRM was Pedro’s patch, having driven for it in 1968 and scored in 1970 – at his beloved Spa – its first GP win for four years. It was Pedro who chatted affably with the mechanics and Jo who remained aloof.

Intriguingly, at JWA, it was Pedro who kept the quieter counsel and Jo who liked to down a couple of beers at lunch during test days, leap over pit counters and generally set the tone.

Always respectful of each other, they assumed nothing and expected to reap only what they sowed.

Jo had the edge in qualifying in the 1970 sports car season, but it was Pedro who won four races to his ostensible team leader’s three.

The following year the score was 4-1 in the Mexican’s advantage.

He was also 4-1 ahead by the time their F1 qualifying head-to-head had reached midseason.

Plus Pedro had caught the eye with a ferocious part in perhaps the greatest wet-weather duel: versus Jacky Ickx’s ultimately victorious Ferrari at Zandvoort.

It was Jo who joshed about a little Mexican bastard trying to kill him. It was Pedro who was in no need of leavening jokes as he perpetrated a slow strangulation rather than the crime of passion alluded to. His speed, consistency, mechanical sympathy and paucity of crashes combined to form a relentlessness that even fearless, workaholic Jo could not quite match.

At Österreichring in June, Pedro conjured another miracle victory, this time by charging on slicks in the rain to obviate pit stops after dropping three laps while a voltage regulator was changed.

He was at his best, then – two weeks before his unnecessary death in an inconsequential race.

When asked why he planned to contest that fateful Interserie encounter at the Norisring in a privateer Ferrari, he had answered simply that he needed the money.

Needed the ‘fix’ more like – in the same way that Siffert had bought a Formula 2 Chevron to fill what few gaps his F1, WSC and Can-Am programmes left him.

Pedro’s death released something inside Jo. He moved forward a couple of rows in GP qualifying and revived flagging BRM’s morale with a convincing victory from pole at the Österreichring despite a slow puncture late in the race.

He finished second at Watkins Glen, too.

He was at his best, then – three weeks before his unnecessary death in an inconsequential race.

The supposedly celebratory Victory Race at Brands Hatch was his 41st outing of the season. It felt like one too many – but still he put his BRM P160 in pole.

He was recovering from a weary start when his car snapped beyond his control on the approach to Hawthorns. The cause was inexplicable. The rescue response was inexcusable. And 50,000 attended his funeral.

A lot has changed since – praise be! – but there is still some crossover between then and now. For Switzerland read Somerset. For Pedro read Sergio (or ‘Checo’ – depends how well you know him, I guess). For Jo read Jenson. And for murder read ‘Move over!’

The tracks have gone soft – from Eau my God! to deserts of Bahraini room – but these little Mexicans are still hard bastards.

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