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The neutral, homoleptic pyridylphosphininenickel(0) complex [Ni(2-Py-4,6-Ph 2 -PC 5 H 2 ) 2 ] ( 1 ) has been obtained by reaction of the formal Ni(0) source [(IPr)Ni(H 2 C═CHSiMe 3 ) 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 ]BF 4 , [ 1 (THF)]PF 6 , and [ 1 2 ](BAr F 4 ) 2 . The structures of these salts reveal an interesting dependence on the nature of the anion. While [ 1 ]BF 4 and [ 1 (THF)]PF 6 show trigonal-bipyramidal coordination of Ni in the solid state, [ 1 2 ](BAr F 4 ) 2 exists as a dinuclear Ni(I) complex and possesses a bridging phosphinine moiety in a rare μ 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 λ 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.