Nestled SELECT in FROM problem

(SELECT MAX(LC) FROM

(SELECT COUNT(Y.lagId) AS LC
FROM Arena AS A2, Match AS M2, (SELECT DISTINCT lagId FROM LagDeltagande AS LD2 WHERE LD2.lagId=M2.Id) AS Y

WHERE M2.aPStad=A2.pNamn
AND M2.aPLand=A2.pLandNamn
AND M2.aNamn=A2.namn));

SELECT MAX(LC) AS max_lc
  FROM ( SELECT LD2.lagId
              , COUNT(*) AS LC
           FROM Arena AS A2
         INNER
           JOIN Match AS M2
             ON M2.aPStad = A2.pNamn
            AND M2.aPLand = A2.pLandNamn
            AND M2.aNamn  = A2.namn
         INNER
           JOIN LagDeltagande AS LD2 
             ON LD2.lagId = M2.Id
         GROUP
             BY LD2.lagId ) AS Y