Morgan Stanley Smith Barney Spectrum Select (DWSF) 10-Q 2018 Q2 Quarterly report

Exhibit 32.1

CERTIFICATION PURSUANT TO

18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Quarterly Report of Morgan Stanley Smith Barney Spectrum Select L.P. (the “Partnership”) on Form 10-Q for the period ended June 30, 2018 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Patrick T. Egan, President and Director of Ceres Managed Futures LLC, certify, pursuant to 18 U.S.C. § 1350, as adopted pursuant to § 906 of the Sarbanes-Oxley Act of 2002, that:

(1) The Report fully complies with the requirements of section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

(2) The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Partnership.

 /s/ Patrick T. Egan                            

 Patrick T. Egan

 Ceres Managed Futures LLC

 President and Director

Date: August 9, 2018