Sec. 5. Except as provided in sections 6 and 7 of this chapter, a Medicaid recipient may not receive physician services from a provider other than the managed care provider selected by the recipient under section 2 of this chapter, except as follows:
(1) In an emergency.
(2) Upon the written referral of the managed care provider.
(3) As provided in sections 6 through 9 of this chapter.