Instead of using split, you could capture the parts into $1 and $2 via a regex: 
use strict;
use warnings;
use Data::Dumper;

my @array;

while (<DATA>) {
   my ($time,$id) = /([\d:.]+)\D+(\d+)/;
   push @array, "$id:$time";
}

print Dumper \@array;

__DATA__
00:00:00.20 - blah blah perl him me it they 0223503 blah blah blah
00:00:00.30 - blah blah perl him me it they 0223504 blah blah blah

[download]
UPDATE:
OK, i see what's going on. You split up the line and get back the parts you want, but when you push them to the array, you are pushing a list, not a single value. Try this: 
while (<IN>) {
   push @array, join('#',(split)[9, 0]);
}

[download]
or more cleverly: 
my @array = map join('#',(split)[9, 0]), <IN>;

[download]
NOTE:
This reply was originally posted to (DUPE) Splitting two columns into an array. The last two code snippets above joined on a colon (:), which i changed to a pound sign (#) for this question.

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to (jeffa) Re: Splitting two columns into an array by jeffa
in thread Another array thing - split two fields into one by Anonymous Monk

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