The neutral, homoleptic pyridylphosphininenickel(0) complex [Ni(2-Py-4,6-Ph (2)-PC5H2)(2)] (1) has been obtained by reaction of the formal Ni(0) source [(IPONi(H2C=CHSiMe3)(2)] with 2 equiv of 2-(2'-pyridyl)-4,6-diphenylphosphinine (L). Compound 1 can be oxidized both electrochemically and through the use of ferrocenium salts, to afford the corresponding Ni(I) complexes [1]BF4, [1 (THF)]PF6, and [1(2)](BAr4F)(2). The structures of these salts reveal an interesting dependence on the nature of the anion. While [1]BF4 and [1 (THF)]PF6 show trigonal-bipyramidal coordination of Ni in the solid state, [1(2)](BAr4F)(2) exists as a dinuclear Ni(I) complex and possesses a bridging phosphinine moiety in a rare mu(2) mode. Reactions of 1 with 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 1 with bromobenzene affords the lambda(5) phosphinine 2 and the bipyramidal Ni(I) complex [1]Br, whereas a more unconventional oxidation product 3 is formed from the reaction of 1 and iodobenzene.