Hamilton's hopes of signing off from McLaren at the end of the year with a second world title in his pocket are effectively over as the result in Yeongam left him 62 points adrift of new championship leader Sebastian Vettel with only a maximum of 100 up for grabs.
His Korean challenge was undone by a rear anti-roll bar failure during his first stint, which had a dire effect on the car's handling and destroyed its tyres at an vastly accelerated rate.
It left the Briton as the only man who needed to make three stops during the 55-lap race as he slowly fell back from fourth place, despite his best efforts to fight with Kimi Raikkonen, Nico Hulkenberg and Romain Grosjean as they took advantage of his woes.
Even after his final stop Hamilton was threatening to catch and pass the Toro Rossos of Jean-Eric Vergne and Daniel Ricciardo, only to pick up a piece of loose Astroturf and fall back.
But, having had to deal with so many problems, Whitmarsh was in no doubt about the quality of the 2008 world champion's performance.
He said: "I thought it was going to be very unlikely he would get to the end of the race because I thought he would probably consume all the tyres we had available for him.
"He showed really heroic fighting spirit to do a job, despite what a terrible day it is I have to come away incredibly proud of him and what he did in the circumstances to fight.
"He was fighting with Kimi and Grosjean and ultimately - after his third stop - catching the Toro Rossos and he should have been able to get past them when he collected two to three square metres of Astroturf on the car as well which he had to contend with for the last few laps.
"Most things that could go wrong did go wrong. I think he showed fantastic spirit and grit to get to the end and get the most hard-fought world championship point I can remember in the history of this team.
"For one point you don't get much more heroic a drive.
"That's the inspiration I will take away from Korea, I will try and forget lots of it, but the way in which he fought for that was fantastic."
It was an even worse day for Hamilton's team-mate Jenson Button. Having started 11th the 2009 world champion only got as far as turn three, where he and Nico Rosberg were assaulted by the wayward Sauber of Kamui Kobayashi, who received a drive-through penalty for his trouble.
And Button was also unimpressed with the driving of his future team-mate Sergio Perez.
"I was braking for the first corner and Sergio braked really late and he didn't hit me, but he hit the car in front of me and broke something off the back of that car, so I had to run wide and push Nico (Rosberg) off the circuit.
"I don't know what happened then, I braked really late for turn three and saw a car flying over the top of mine and it was a Sauber again.
"It's pretty poor driving standards considering this is the pinnacle of motor sport.
"I don't know what they are doing out there, I don't know how Kobayashi managed to hit two of us under braking, it was pretty special of him."