Alternatively, you can change the definition of a field.

use strict;
use warnings;

use Sort::Fields;
use Data::Dumper;

my @data = ( "  56 1752.eps", "  56 2613.eps", "  56 3469.eps",
"   8 INPUT000", "  16 INPUT001", "  16 INPUT002", "  96 MTA.1.ps",
"  96 MTA.6.ps", "  80 MTA.7.ps", "  32 head.eps", "   8 labs",
"   0 lib", "   8 mkexe.bat", " 112 out", "   0 screenshots",
"8720 trace.exe", "  16 trace.pl", "   8 tracehosts",
"1160 trace.041409.exe", "1160 trace.orig.exe",
);

my @sorted = fieldsort( "".qr/(?<!^)(?<!\s)\s+/, ['1n'], @data);
print(Dumper(\@sorted));
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