hmmm, If the exact same query text runs ok through phpmyadmin then it's back to first principles. Let's make sure you are making the connection OK, that you have the right databse selected and that the query is using the connection id to the database.
try this:
$db_link_id = mysql_connect ("localhost",$username,$password);
if (!db_link_id) die ("unable to connect to mysql");
if (!mysql_select_db($dbname,$db_link_id) die ("unable to select database $dbname");
$query=" SELECT * FROM WTLtest WHERE Team = 'ATL'";
$result = mysql_query($query, $db_link_id);
if (!result) echo "still no result from query";
$num = mysql_num_rows($result);
mysql_close();
The first two lines ensure we know what the link id is for the connection you make. If the connection fails you'll get a simple message. Note the host is now a string, although if this was the problem it would have failed on parse. The next line ensures you connect to the database you want.Note the inclusion of the database name in the select with the var $dbname - you will need to set this. You will notice that I have an aversion to assuming defaults they nearly always get you in the end. The query statement now explicitly uses the connection id. The next statement merely checks to see of there was a result. Hopefully this will either point out the problem or even fix it. My bet is on the selection of the database.
Hope this helps,
Cris