Another nut to crack with insertion into tables... *sigh*

insert into Rollenspiel
(Name, HerstellerID, Erscheinungsdatum,
Bestellnummer, Preisempfehlung,
Beschreibung,
Computertyp, Datentraegertyp,
System, AnzahlCharaktere, Typ,
Cluebook, SpielstandEditor)
values
('Might & Magic I', (select HerstellerNummer from Hersteller
where Name like '%Blueborg%'), '17.03.1986',
'role01', '29,50',
'{"Einfach irgendeine Beschreibung halt..."}',
'{"PC", "Mac", "c64", "Atari"}', '{"Diskette", "CD"}',
'Freies System', 6, 'Fantasy',
'{"Solution to Might & Magic Series", "The Might & Magic I Solution"}',
'{"http://www.mightandmagic.de/I/editors.html"}');
ERROR: parser: parse error at or near "select"

The question is: why?

spiele=> select HerstellerNummer from Hersteller;
herstellernummer
----------------
1
2
30
31
32
4
5
6
7
8
66
70
99
17
88
(15 rows)

Doing this from psql plainly yields the wanted result:

spiele=> select HerstellerNummer from Hersteller where Name like '%Blueborg%';
herstellernummer
----------------
7
(1 row)

Pointers to FAQs, solutions, help, donuts greatly appreciated ;-)