use autodie;
my (%used, %player);
open $player{$_}, '<', "$_.txt" for qw( DR DL DC SW );
open my $formation, '<', 'formation.txt';
for my $position (<$formation>) {
        chomp $position;
        while (readline $player{$position}) {
                my ($name) = split;
                next if $used{$name};
                $used{$name} = 1;
                last;
        }
        print $position, ' ',  $_ // "NoPlayer\n";
}

##</code><code>##

SW Varane,114.75
DR Arbeloa,149
DC Ramos,169
DC Pepe,163
DL Marcelo,148.5
SW Pepe,65.2
DR Carvajal,146
DC Varane,153
DC Nacho,134
DL Coentrao,148

##</code><code>##

SW Varane,114.75
DR Arbeloa,149
DC Ramos,169
DC Pepe,163
DL Marcelo,148.5
SW Nacho,60.3
DR Carvajal,146
DC NoPlayer
DC NoPlayer
DL Coentrao,148