#!/usr/bin/perl -w
use strict;
use Benchmark;
use vars qw($myvar $result $a $b $c $d);
$myvar = "one,two,three,four";

timethese(1000000, { 
    Regex  => '$a=$1, $b=$2, $c=$3, $d=$4 if $myvar   =~ /^[^,]+,([^,]+),[^,]+,[^,]+$/',
    Split1 => '$result = (split /,/, $myvar)[1]',
    Split2 => '$result = (split /,/, $myvar, 4)[1]',
    Split3 => '$result = (split /,/, $myvar, 3)[1]'
});

Benchmark: timing 1000000 iterations of Regex, Split1, Split2, Split3...
     Regex: 26 wallclock secs (25.75 usr +  0.00 sys = 25.75 CPU)
    Split1: 16 wallclock secs (16.31 usr +  0.00 sys = 16.31 CPU)
    Split2: 16 wallclock secs (16.15 usr +  0.00 sys = 16.15 CPU)
    Split3: 13 wallclock secs (12.74 usr +  0.00 sys = 12.74 CPU)