for my $i ( 0 .. $#$eventscores ) { # forces readonly 
    for ( my $j = $i;
          $j <= $#$eventscores;
          $j++ ){ 
        if ( $eventscores->[$j][0] == $eventscores->[$i][0] ) {
            push (@scores, $eventscores->[$j][2] );
        }
    }
    # more code unrelated to loop
}