sine qua non of an antitrust claim is injury to competition.”) (emphasis in original), reh’g granted, (Oct. 9, 2001). In other words, SWBT was entitled to be heard by a jury on the allegation that it lacked the power to control market prices or exclude competition vis-a-vis the relevant market it contended for. See Aplees. Sim Reply Br. at 6 (arguing that monopoly claim verdict could be affirmed on either theory); see also Beville, 39 P.3d at 760 (“Market power is the preliminary threshold inquiry and is often dispositive of antitrust cases.”). One need not accept SWBT’s monopsony argument to conclude that the relevant market should have been decided by the jury, not the district court. See Spectrum Sports, Inc. v. McQuillan, 506 U.S. 447, 459, 113 S.Ct. 884, 122 L.Ed.2d 247 (1993) (<HOLDING>). The evidence plainly “present[ed] a
holding that a plaintiff claiming monopolization is obligated to establish the relevant market because the power to control prices or exclude competition only makes sense with reference to a particular market holding that changes in the baseball card market between 1965 and 1980 foreclosed any argument that a definition of the relevant market by the federal trade commission could preclude relitigation of the market definition issue recognizing implied duty to market recognizing that the burden of proof is an essential element of the claim itself and that one who asserts a claim has the burden of proof that normally comes with it holding that proof of relevant market is essential under  2