In Spanish Seville, the 26-year-old made his debut at the distance, set a Swedish record, 2.07.36, and qualified for the Paris Olympic Games.
The race in the French capital was, however, something else.
And a moment after crossing the finish line, the Swede was bent double and holding his thighs.
I'm pretty tired. It was hilly, that's what I can say. Even more than I expected. The hill at 28 kilometers... It shouldn't be legal to have such a one, he says.
"All in"
Hassan bet everything from the start, was good in the beginning and was at best in 26th place.
In the end, he crossed the finish line in the Invalides area as the 28th runner.
The feeling?
Satisfied – and dissatisfied.
With hindsight, I might have been a bit more cautious in the hills to have more strength at the end, he says.
But I regret nothing. At an Olympic Games, you really have to clench your fist and go "all in".
How well did you know the course?
I had read about it but not run it. Such hills I've never run before. You never got to run on, it was up and down all the way.
Suldan Hassan, who started with athletics eleven years ago, was in Paris to chase the perfect marathon.
Part of it was about fluids, as he, due to his visual impairment, could only drink at two of the eight stations in Seville.
On the French streets, he missed no water.
There, I have no excuses. They did a fantastic job; Yannick Tregaro at the first, Kajsa Bergqvist at the last and Andreas Almgren at 35 kilometers. Everyone did a fantastic job all the way, he says.
But if you run a marathon, you get tired regardless of whether you take drinks or not.
Aiming for Los Angeles
Suldan Hassan says he is more muscularly tired compared to the race in Seville.
Still, he is confident.
The runner has found his distance.
Now, he is aiming to get better, gain more routine, and is targeting the World Championship in Tokyo next year and the Olympic Games in Los Angeles 2028.
Tamirat Tola from Ethiopia finished with an Olympic record of 2.06.26 – and was 4.55 ahead of Suldan Hasan.