If it's single player then you just need to not press space before saving. If you're on a laptop it's possible you're accidentally catching a hotkey (some have space + another key mapped onto them)
If it's multiplayer then you just have to be quick to save or use autosave to guarantee getting it.
<Erf> SkulFuk: gf just made a toilet sniffing joke at me
<Erf> i think
<Erf> i think i hate you