Exhibit 99.1350CERT


     Certification Pursuant to Rule 30a-2(b) under the 1940 Act and
                  Section 906 of the Sarbanes Oxley Act


Pursuant to 18 U.S.C.  1350, the undersigned officer of BlackRock Senior
Floating Rate Fund, Inc. and Master Senior Floating Rate LLC (together, the
"Registrants"), hereby certifies, to the best of his knowledge, that the
Registrants' Report on Form N-CSR for the period ended August 31, 2007, (the
"Report") fully complies with the requirements of Section 15(d) of the
Securities Exchange Act of 1934, as amended, and that the information contained
in the Report fairly presents, in all material respects, the financial
condition and results of operations of each Registrant.


Date: October 22, 2007


/s/ Robert C. Doll, Jr.
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Robert C. Doll, Jr., Chief Executive Officer (principal executive officer) of
BlackRock Senior Floating Rate Fund, Inc. and Master Senior Floating Rate LLC


Pursuant to 18 U.S.C.  1350, the undersigned officer of BlackRock Senior
Floating Rate Fund, Inc. and Master Senior Floating Rate LLC (together, the
"Registrants"), hereby certifies, to the best of his knowledge, that the
Registrants' Report on Form N-CSR for the period ended August 31, 2007, (the
"Report") fully complies with the requirements of Section 15(d) of the
Securities Exchange Act of 1934, as amended, and that the information contained
in the Report fairly presents, in all material respects, the financial
condition and results of operations of each Registrant.


Date: October 22, 2007


/s/ Donald C. Burke
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Donald C. Burke, Chief Financial Officer (principal financial officer) of
BlackRock Senior Floating Rate Fund, Inc. and Master Senior Floating Rate LLC



This certification is being furnished pursuant to Rule 30a-2(b) under the
Investment Company Act of 1940, as amended, and 18 U.S.C. Section 1350 and is
not being filed as part of the Form N-CSR with the Securities and Exchange
Commission.