The reaction of di-2-pyridyl ketone, (2-py)2CO, with Ni(O2CMe)2·4H2O yields the cage [Ni9(OH)2(O2CMe)8{(2-py) 2CO2}4], which reacts further with N3− ions to give the structurally similar cluster [Ni9(N3)2(O2CMe)8 {(2-py)2CO2}4] containing extremely rare η1,μ4-N3− groups; magnetic studies reveal that the spin ground state of the latter is nine times the ground state of the former.