Power of Attorney

        Know all by these presents that the undersigned does hereby make,
constitute and appoint each of Karen M. McCarthy, Michael Nathenson and Larry
Miller, or any one of them, as a true and lawful attorney-in-fact and agent of
the undersigned, with full powers of substitution and revocation, for and in the
name, place and stead of the undersigned (in the undersigned's individual
capacity), to execute and deliver such forms that the undersigned may be
required to file with the U.S. Securities and Exchange Commission as a result of
the undersigned's ownership of or transactions in securities of Blue Buffalo Pet
Products, Inc. (i) pursuant to Section 16(a) of the Securities Exchange Act of
1934, as amended, including without limitation, statements on Form 3, Form 4 and
Form 5 (including any amendments thereto), and (ii) in connection with any
applications for EDGAR access codes or any other documents necessary or
appropriate to obtain codes and passwords enabling the undersigned to make
electronic filings with the Securities and Exchange Commission, including
without limitation the Form ID. This Power of Attorney shall remain in full
force and effect until the undersigned is no longer required to file Forms 3, 4
and 5 with regard to the undersigned's ownership of or transactions in
securities of Blue Buffalo Pet Products, Inc., unless earlier revoked in
writing. The undersigned acknowledges that Karen M. McCarthy, Michael Nathenson
and Larry Miller are not assuming any of the undersigned's responsibilities to
comply with Section 16 of the Securities Exchange Act of 1934.

                                       By:   /s/ Michael A. Eck
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                                             Michael A. Eck

                                       Date: July 15, 2015
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