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The neutral, homoleptic pyridylphosphininenickel(0) complex [Ni(2-Py-4,6-Ph2-PC5H2)2] (1) has been obtained by reaction of the formal Ni(0) source [(IPr)Ni(H2C═CHSiMe3)2] with 2 equiv of 2-(2′-pyridyl)-4,6-diphenylphosphinine (L). Compound 1can be oxidized both electrochemically and through the use of ferrocenium salts, to afford the corresponding Ni(I) complexes [1]BF4, [1(THF)]PF6, and [12](BArF4)2. The structures of these salts reveal an interesting dependence on the nature of the anion. While [1]BF4and [1(THF)]PF6show trigonal-bipyramidal coordination of Ni in the solid state, [12](BArF4)2exists as a dinuclear Ni(I) complex and possesses a bridging phosphinine moiety in a rare μ2mode. Reactions of 1with halobenzenes highlight the noninnocent behavior of the aromatic phosphinine ligand, leading to the formation of oxidized Ni complexes but not to classical oxidative addition products. The reaction of 1with bromobenzene affords the λ5phosphinine 2and the bipyramidal Ni(I) complex [1]Br, whereas a more unconventional oxidation product 3is formed from the reaction of 1and iodobenzene.