excel - Google Sheets - REGEXEXTRACT -

i've tried while , can't find way extract names out of e-mailadress format this: "peter.johnson@mail.com". when use following execution:

=regexextract(a1, "(.*)\.(.*)@") 

it outputs: "peter" "johnson" 2 seperate cells.

what want "peter johnson" 1 cell.

this testsheet. appreciated. https://docs.google.com/spreadsheets/d/1pn2ger6hjubu2pyuhflifebfqhfnfeuvdncdvwyn_jo/edit?usp=sharing

i found function join doing research in how combine 2 cells. correct formula now:

=join(" ",regexextract(a1, "(.*)\.(.*)@")) 

which outputs: "peter johnson".

i'll leave spreadsheet shared example.