Mario Andretti is another F1 driver to do other events like open wheel racing in the USA and Le Mans numerous times, one attempt with his son and Phillipe Alliot in 956-101 and then also with the Porsche factory in 1988. If I remember right he was quite heavily involved in the single turbo Porsche 962 for IMSA races in America.
Mario also gave the Porsche factory a heck of a lot of knowledge of American open wheel racing, which they unfortunately frittered away with poor car development choices and less than ideal management decisions.
Mario was willing to hop in, drive and win in anything, which is a big part of his legend, and is among the undisputed greats of all time, but his time in sports car, and that period in particular wasn't a highlight of his career.
The legend of the 962, in IMSA's Camel GT days, rested first with Al Holbert, and his co-driver Derek Bell. They were the team to beat. Holbert was the first to lead Porsche Motorsport North America, and responsible for building an evolution of the 962 chassis entirely in the U.S. Alwin Springer built the engines in his ANDIAL shop in Southern California and is also a P-car legend.
Holbert was killed in a small plane crash, which put a premature end to that run, but even if that hadn't occurred, Nissan's ZX-T, built down the road in Vista by NPTI, powered by Electramotive's engines, and driven by Geoff Brabham, were rising to the challenge, and later Dan Gurney's AAR Eagle-Toyota Mk3, with Fangio at the helm, would come to dominate, in the latter stages of the 962's life.
The underbody concepts in the those Eagles later served as inspiration for the ill-fated Nissan GT-R LM NISMO, and have indirectly carried forth even to more recent times, with the original wingless incarnation of the Peugeot 9X8 in the WEC.
Those were heady times for IMSA, when both the prototype and sub-class fields were large enough to merit holding separate races. And who can forget Audi building a tube-frame silhouette 90 with AWD, and finding much success in GTO and Trans-Am.
It's no mistake that IMSA revived the GTP name for its current top class, to try to evoke that time.
Let's see, here. Take Jim Clark, Graham Hill, Mario Andretti, Emerson Fitipaldi, Jacques Villeneuve and Juan Pablo Montoya. All six won Indy, and all but Montoya are former WDCs. Are Graham Hill and Mario the only two to ever compete at LeMans? I'm sure that if you dug deeper, there are more examples of drivers to complete this mythical triple crown. So you can forget Alonso being only the second.
These trophies, though mythical, are not participation trophies.
Tennis players can complete "career" Grand Slams, but the highest honor is reserved for those who win all the major tournaments in a single season. Similarly, the original Triple Crown is bestowed to the horse than wins the Derby, Preakness, and Belmont in a single season.
It is difficult, in not practically impossible to win all the EGOT awards (Emmy, Grammy, Oscar, Tony) in a single season, so it is also a careeer achievement.
The operative word is
win, not just compete, or be nominated.
Nick Tandy is the latest driver to achieve the endurance racing Triple Crown (Daytona, Sebring, Le Mans) this season. He can also claim a Petit Le Mans win, in a GT car no less, on his CV.
To date, Graham Hill is the only driver to achieve the racing Triple Crown (Indy 500, Le Mans, WDC/Monaco depending on your definition) by winning all three.
Alonso was the latest to make the attempt to become the second.
In any case, this is an F1 thread, so if anyone wishes to continue this discussion, they area free to create a more sports car racing, or more general racing topic.