Here we extend the research of the (R,Ca)MnO3 perovskites to the smallest-R end member (Lu,Ca)MnO3. Magnetic and magnetotransport properties of the (Lu1−xCax)MnO3 system are systematically investigated in regard to carrier doping. It is found that hole doping into the antiferromagnetic x=0.0 phase, LuMnO3, causes a spin-glass-like magnetic competition in the wide doping range of 0.1≤x≤0.6, whereas electron doping into the antiferromagnetic x=1.0 phase, CaMnO3, induces a large magnetoresistance effect for 0.8≤x≤0.95.Peer reviewe