Ludger Beerbaum and Gotha. © Karl-Heinz Frieler/FEI
Beerbaum won a Mercedes four-wheel-drive for his win, as well as a Rolex watch.
A very tough five-star course designed by Christa Jung led to eight top riders retiring without completing the first round.
The German course designer stretched the riders from the first fence to the last, and the eight retirements on course were testament to the degree of difficulty.
In the smallest World Cup jump-off field seen this season, the half dozen qualifying riders from the starting field of 39 went all-out for time against the clock following the opening clear round by Switzerland's 24 year-old Janika Sprunger and Uptown Boy.
Another 15 would jump before she was joined by Ireland's Denis Lynch and Abbervail van het Dingeshof, and then reigning individual European Champion, and the man who won the third leg of the current Rolex season in Lyon, France last month - Sweden's Rolf-Goran Bengtsson - followed suit with Quintero La Silla.
The home crowd could at last heave a sigh of relief when Marco Kutscher brought Cornet Obolensky home without incident. With 15 German representatives in the line-up they had watched many fail to make the cut, including three-time World Cup title-holder Marcus Ehning who retired Noltes Kuchengirl after leaving four fences on the floor. But when Beerbaum earned his place in the decider alongside his fellow-countryman, and Steve Guerdat did likewise with Nino des Buissonnets, then a clash of titanic proportions was guaranteed in the race against the clock.
"It was not too technical but it was quite big - Christa did a good job," Beerbaum said afterwards. "There were mistakes at all the fences, except, I think, the first - it was selective," he added.
Madeleine Winter-Schulze's 10-year-old mare, Gotha, has been going from strength to strength in the hands of the five-time Olympian in recent months, and produced a superb jump-off round to clinch maximum points for the 48 year-old veteran who won the prestigious series title 18 years ago.
For Beerbaum, there was plenty to celebrate. "This is my fifth time to win the Grand Prix in Stuttgart and the second time with Gotha - I won with her here two years ago," he said. Talking about the jump-off he said "I expected there would be eight or ten riders in it, but with the six that got through I knew it would be fast enough and I couldn't relax knowing that Steve was coming into the arena after me."
He plans now to compete at the Global Champions Tour Final in Abu Dhabi next weekend, and then the next leg of the Rolex FEI World Cup Jumping series in Geneva, Switzerland in early December. "But Gotha will have a bit of a break now - she deserves it!" said the rider who has moved into sixth place on the series leaderboard.
The result sees Bengtsson now taking taking over at the top of the Western European League League followed by Swiss riders Pius Schwizer in second and Steve Guerdat in third. Great Britain's Nick Skelton has collected 37 points on the US circuit in recent months and currently lies fourth ahead of Ireland's Denis Lynch in fifth.