MediaOne Group, Inc.
Suite 700
5613 DTC Parkway
Englewood, Colorado 80155
(303) 858-3511
Stephen E. Brilz
Corporate Counsel and Assistant Secretary
 
                                 June 18, 1998
 
MediaOne Group, Inc.
188 Inverness Drive West
Englewood, Colorado 80112
 
                     Re: Public Offering of Debt Securities
 
Gentlemen and Ladies:
 
    I have examined the Registration Statement on Form S-3 filed
contemporaneously herewith (the "Registration Statement") by MediaOne Group,
Inc. (the "Registrant"), with the Securities and Exchange Commission (the
"Commission") in connection with the registration under the Securities Act of
1933, as amended, of up to $1,500,000,000 of debt securities (the "Debt
Securities"). I have examined the Registrant's certificate of incorporation and
bylaws, as amended, the form of indenture by and between the Registrant and The
First National Bank of Chicago, as Trustee, under which any debt securities are
to be issued (the "Indenture"), and such other documents, certificates and
matters of fact as I have deemed necessary for purposes of this opinion. I am
familiar with the proceedings taken and proposed to be taken by the Registrant
in connection with the proposed authorization, issuance and sale of the Debt
Securities.
 
    I am also familiar with the proposed opinion of legal counsel qualified to
practice in New York concerning the validity, legality, and binding effect of
any debt securities under New York law, upon which opinion I will rely, at such
time as Debt Securities are issued in connection with the Registration
Statement.
 
    Based upon the foregoing, and in reliance thereon, it is my opinion that,
subject to the receipt of payment for the Debt Securities and subject to the
terms of the Debt Securities being otherwise in compliance with then applicable
law, when the Debt Securities have been duly authorized, executed,
authenticated, if necessary, and delivered in accordance with the terms of the
applicable resolutions of the Board of Directors of the Registrant, and any
legally required consents, approvals, authorizations, and other orders of the
Commission or of any other judicial or regulatory authorities have been
obtained, the Debt Securities will constitute legally issued and binding
obligations of the Registrant, except as may be limited by bankruptcy,
insolvency, reorganization, moratorium, or similar laws affecting creditors'
rights generally, and except that the remedies of specific performance and
injunctive and other forms of equitable relief are subject to certain equitable
defenses and to the discretion of the court before which any proceeding therefor
may be brought.
 
    I hereby consent to the filing of this opinion as an exhibit to the
Registration Statement, and I further consent to the use of my name under the
caption "Legal Opinions" in the Prospectus forming a part of the Registration
Statement.
 
                                          Very truly yours,
                                          /s/ STEPHEN E. BRILZ
                                          Stephen E. Brilz