Kept it going for 1:47.35 meaning 19.18km. Was a bit too motivated meaning that I went out way too fast (more like a 10km pace than one for double the distance). Managed to keep it going for about 11km after which I started to strugle, meaning somewhat slower speed. Kept fighting until about 16,5km. Then I had to walk for a bit. When I saw that I still had a decent distance to the chasing "car", I gave it a go for a km and then another one.
I guess with some better pacing, I could already do a half marathon now. But it'll wait for 1½ month.
Now I'm just following my team captain, Camilla Pedersen who has passed the marathon