I am trying to understand the order in the following text.

> 
> In einem Laufwettbewerb beendete Gabi das Rennen in 1 Stunde. Fabian kam in 13 Minuten mehr, Gregor in 8 Minuten weniger an.
> 
> 
> 

It is not clear to me if Gregor finished 8 minutes less than Fabian or 8 minutes less than Gabi.

Shouldn't we use "als" to be more precise or is there something I am missing in the text?