Simply use an alias to tell RedBeanPHP what 'v' and 'l' are.
Here is how:
//for testing only...
list($team1, $team2) = R::dispense('team', 2);
$game = R::dispense('game');
$game->team = R::load('team',$team1);
$game->visitor = R::load('team',$team2);
$id = R::store($game);
$theGame = R::load('game', $id);
echo 'team1: '.$theGame->team->id;
echo PHP_EOL;
//here I tell RedBeanPHP: visitor IS a team.
echo 'team2: '.$theGame->fetchAs('team')->visitor->id;
For more details concerning aliasing: http://www.redbeanphp.com/aliasing
Hope this helps!
Cheers, Gabor