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                                                                     Exhibit 8.2

                               MANATT TAX OPINION

July 21, 2004                                                File No:  25907-031

Slippery Rock Financial Corporation
100 South Main Street
Slippery Rock, Pennsylvania 16057

       RE: CERTAIN FEDERAL INCOME TAX CONSEQUENCES OF THE MERGER OF
           SLIPPERY ROCK FINANCIAL CORPORATION WITH AND INTO F.N.B. CORPORATION

Ladies and Gentlemen:

      In accordance with the request of Slippery Rock Financial Corporation, a
Pennsylvania corporation ("Slippery Rock"), we provide the following analysis
and opinions relating to certain federal income tax consequences of the merger
(the "Merger") of Slippery Rock with and into F.N.B. Corporation, a Florida
corporation ("Parent"). Immediately following the Merger, Slippery Rock's
wholly-owned subsidiary, The First National Bank of Slippery Rock, a national
association ("Slippery Rock Bank"), shall merge (the "Bank Merger") with and
into Parent's wholly-owned subsidiary, The First National Bank of Pennsylvania
("Parent Bank"). The Merger and the Bank Merger will be undertaken pursuant to
that certain Amended and Restated Agreement and Plan of Merger dated as of July
15, 2004, including exhibits thereto (the "Agreement"). This opinion is being
delivered in accordance with Section 7.02(c) of the Agreement. Terms used herein
have the same meanings as in the Agreement.

      The following description of the Merger is set forth in the Agreement.
Subject to the terms and conditions of the Agreement, at the Effective Time,
Slippery Rock shall merge with and into Parent in accordance with the applicable
provisions of the Pennsylvania Business Corporation Law of 1988, as amended, and
the Florida Business Corporation Act, as amended. The separate corporate
existence of Slippery Rock shall cease and Parent shall survive and continue to
exist as a corporation incorporated under the Florida Business Corporation Act.
Parent shall be the Surviving Corporation. The name of the Surviving Corporation
shall be "F.N.B. Corporation." The articles of incorporation and bylaws of the
Surviving Corporation immediately after the Merger shall be the articles and
bylaws of Parent as in effect immediately prior to the Merger. The executive
officers of the Surviving Corporation immediately after the Merger shall be the
executive officers of Parent immediately prior to the Merger, each of whom shall
serve until such time as their successors shall be duly elected and qualified.
The authorized capital stock of the Surviving

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Slippery Rock Financial Corporation
July 21, 2004
Page 2

Corporation upon consummation of the Merger shall be as set forth in the Parent
articles of incorporation immediately prior to the Merger.

      At the Effective Time, the effect of the Merger shall be as provided in
the applicable sections of the Pennsylvania Business Corporation Law and the
Florida Business Corporation Act. Without limiting the generality of the
foregoing, and subject thereto, at the Effective Time, all the property, rights,
privileges, powers and franchises of Slippery Rock shall vest in the Surviving
Corporation, and all debts, liabilities, obligations, restrictions, disabilities
and duties of Slippery Rock shall become the debts, liabilities, obligations,
restrictions, disabilities and duties of the Surviving Corporation.

      Subject to the provisions of the Agreement, each share of Slippery Rock
Common Stock issued and outstanding immediately prior to the Effective Time
(other than Dissenting Shares and Treasury Stock) shall, by virtue of the
Merger, no longer be outstanding and shall, as of the Effective Time,
automatically be converted into and shall thereafter only represent the right to
receive, at the election of the holder thereof, any of the following: (a) Parent
Common Stock equal to the Exchange Ratio; (b) cash in the amount of the Price
Per Share; or (c) a combination of Parent Common Stock and cash. The Agreement
sets forth the procedures for making elections and allocations of such merger
consideration. At and after the Effective Time, each share of Treasury Stock
shall be canceled and retired and no shares of Parent Common Stock, cash, or
other consideration shall be issued in exchange therefor. At and after the
Effective Time, each share of Parent Common Stock issued and outstanding
immediately prior to the Effective Time shall remain issued and outstanding and
shall not be affected by the Merger.

      Except as discussed below, no fractional shares of Parent Common Stock
shall be issued in the Merger. In lieu thereof, each holder of Slippery Rock
Common Stock who would otherwise be entitled to receive a fractional share of
Parent Common Stock (after taking into account all Certificates delivered by
such holder) shall receive an amount in cash (without interest) rounded to the
nearest cent, equal to the product obtained by multiplying (a) the Parent
Closing Average by (b) the fraction (calculated to the nearest ten-thousandth)
of the share of Parent Common Stock to which the holder would otherwise be
entitled. No such holder shall be entitled to dividends, voting rights or any
other rights in respect of any fractional share interest. Any Slippery Rock
shareholders who elect to enroll in Parent's dividend reinvestment and stock
purchase plan will receive, in book entry form, the exact number of shares,
rounded to three decimal places, of the Parent Common Stock to which such
Slippery Rock shareholder is entitled.

      Any holder of Slippery Rock Common Stock who shall be entitled to be paid
the "fair value" of such holder's Dissenting Shares of Slippery Rock Common
Stock, as provided in the Pennsylvania Business Corporation Law, shall not be
entitled to the consideration to which such holder would otherwise have been
entitled (as described above), unless and until such holder shall have failed to
perfect or withdrawn or lost such holder's dissenter's rights under the
Pennsylvania Business Corporation Law, and shall be entitled to receive only
such payment as is provided for in the Pennsylvania Business Corporation Law.



Slippery Rock Financial Corporation
July 21, 2004
Page 3

      Immediately following the Merger, Slippery Rock Bank shall merge with and
into Parent Bank pursuant to the Bank Merger Agreement. Parent Bank shall
continue as a wholly-owned subsidiary of Parent thereafter.

      Our analysis and the opinions set forth below are based upon the existence
of the facts above and the facts set forth in that certain Agreement referred to
above. Our analysis and opinions are also based on certain representations in
the Agreement and certain written representations to us from Slippery Rock and
Parent in letters of even date herewith (each a "Representations Letter"). Our
analysis and opinions are further based on that certain Amendment No. 1 to Form
S-4 Registration Statement (File No. 333-116526) being filed with the Securities
and Exchange Commission in connection with the transactions described herein
(the "Form S-4"). The facts and representations contained in the
above-referenced documents are incorporated herein by reference as the operative
facts underlying the tax opinions set forth herein. We have assumed, with your
consent, that the statements and representations contained in the Agreement, the
Representations Letters and the Form S-4 are true, correct and complete on the
date hereof and will continue to be true, correct and complete through the
Effective Time of the Merger. Any change or inaccuracy in such facts or
representations may adversely affect our opinions.

      In rendering our opinions, we have examined such documents, laws,
regulations and other legal matters as we have considered necessary or
appropriate for purposes of the opinions expressed herein. In our examination,
we have assumed, with your consent, the genuineness of all signatures on
documents, the capacity of each party executing a document to execute such
document, the authenticity of all documents submitted to us as an original, and
the conformity to original documents of all documents submitted to us as copies.
We also have assumed that the transactions provided for in the Agreement will be
consummated in accordance with the Agreement and that all covenants contained in
the Agreement and the Representations Letters will be performed without waiver
or breach of any material provision thereof. Moreover, we have assumed that any
representation or statement made "to the best knowledge" or similarly qualified
is correct without such qualification, and that the Merger qualifies as a
statutory merger under the Pennsylvania Business Corporation Law and the Florida
Business Corporation Act. We have not made any independent investigation in
rendering our opinions other than as described herein.

      Our opinions are based upon the Internal Revenue Code as of the date
hereof and currently applicable regulations promulgated thereunder (including
final, temporary and proposed regulations), published administrative positions
of the Internal Revenue Service in revenue rulings and revenue procedures, and
judicial decisions. Such legal authorities are all subject to change, either
prospectively or retroactively. No assurance can be provided as to the effect of
any such change upon our opinions. We have undertaken no obligation to update
this letter for events occurring or coming to our attention after the date
hereof.



Slippery Rock Financial Corporation
July 21, 2004
Page 4

      The opinions set forth herein have no binding effect on the Internal
Revenue Service or the courts. No ruling from the Internal Revenue Service has
been or will be sought on any issues related to the transactions provided for in
the Agreement, and there can be no assurance that the Internal Revenue Service
will not take a view contrary to this letter. No assurance can be given that, if
contested, a court would agree with the opinions set forth herein. The opinions
set forth herein represent rather our best legal judgment as to the likely
outcome of the issues addressed herein if such issues were litigated on the
merits and all appeals exhausted.

      In the case of transactions as complex as the transactions provided for in
the Agreement, many federal, state and local income and other tax consequences
arise. We have been asked only to address the issues specifically set forth
below. No opinion is expressed regarding any other issues.

      This letter is being issued solely for the benefit of Slippery Rock and
for the benefit of the Slippery Rock shareholders as of the date of the Merger.
It may not be relied upon by any other person without our prior written consent.

      Subject to the foregoing, it is our opinion that the Merger will
constitute a reorganization within the meaning of Section 368(a) of the Internal
Revenue Code of 1986, as amended (the "Code"). In addition, although the
discussion set forth in the Registration Statement under the heading "Material
Federal Income Tax Consequences of the Merger" does not purport to discuss all
possible United States federal income tax consequences applicable to the
Slippery Rock shareholders as a result of the transactions provided for in the
Agreement, such discussion constitutes our opinion concerning the material
federal income tax consequences applicable to the Slippery Rock shareholders as
a result of the transactions provided for in the Agreement.

      We hereby consent to the filing of this opinion as an exhibit to the
above-referenced Registration Statement on Form S-4 and the reference to the
name of our firm therein. In giving our consent, we do not thereby admit that we
are in the category of persons whose consent is required under Section 7 of the
Securities Act of 1933 or the rules and regulations of the Securities and
Exchange Commission thereunder.

                                            Very truly yours,

                                            /s/ Manatt, Phelps & Phillips, LLP