FLC OF AN MD88 OVERSHOT ASSIGNED DSCNT ALT.

Narrative

CLRED TO CROSS CEDES INTXN AT 11000 FT MSL (NO SPD RESTR). PRIOR TO REACHING CEDES; WE WERE HANDED OFF TO SFO BAY APCH. HE THEN CLRED US TO FLY A HDG TO JOIN THE SFO 095 DEG RADIAL INBOUND AND DSND TO 9000 FT MSL. FO READ BACK THE HDG; RADIAL AND 9000 FT MSL ALT. PASSING THROUGH 9700 FT MSL; THE CTLR STATED THAT; WHILE IT HAD NOT CAUSED A PROB OR CONFLICT; HE SHOWED OUR LAST ALT CLRNC TO BE 11000 FT MSL. HE THEN TOLD US TO MAINTAIN 10000 FT MSL. AS PF; I CANNOT (NOW) DISTINCTLY REMEMBER HEARING THE CLRNC GIVEN TO 9000 FT MSL; BUT I CAN ABSOLUTELY REMEMBER MY FO READING BACK THE 9000 FT CLRNC THAT HE CLAIMS TO HAVE RECEIVED. IN RETROSPECT; I'VE NEVER BEEN CLRED TO ANY OTHER ALT OTHER THAN EITHER 7000 FT MSL OR 11000 FT MSL ON PREVIOUS APCHS INTO THIS ARPT IN THIS VICINITY; SO THAT MIGHT HAVE BEEN A TIP-OFF (HAD I THOUGHT OF IT AT THE TIME). CTLR SHOULD HAVE QUERIED/CAUGHT THE BAD READBACK BY MY FO IF WE WERE NOT CLRED TO 9000 FT MSL BY HIM INITIALLY. ALSO; GIVING A HDG; RADIAL AND ALT ON INITIAL CALL-UP IS CONFUSING -- LENDS ITSELF TO MISSING ONE OR MORE ON EITHER CTLR'S PART AND/OR CREW'S DURING ISSUANCE AND READBACK.