Add 0 padding to single digits at end of filename

Is there a way to Add 0 padding to single digits at end of filename without zeros being added to multiple digit stings at the end of a filename.

For example I want to make filenames like
Excalibur Annual 2.ext
Into Excalibur Annual 02.ext

Without AR making this
X-Men Annual 1995.ext
Into this
X-Men Annual 01995.ext

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Reply to #1:
 
FROM:
Excalibur Annual 1.ext  <----------
Example Text 22.ext
Example Text 333.ext
X-Men Annual 1995.ext

TO:
Excalibur Annual 01.ext  <----------
Example Text 22.ext
Example Text 333.ext
X-Men Annual 1995.ext

Rule:
match a single digit at the end only.   <----------

Use:
Replace Method
(http://www.advancedrenamer.com/user_guide/metho d_replace)

Find: ^(.+) (\d)$
Repl: $1 0$2
[X] Use regular expressions



 

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