Making and breaking bonds in a solid-state compound greatly influences physical properties. A well-known playground for such bonding manipulation is the ThCr₂Si₂- type structure AT₂X₂, allowing a collapse transition where a X−X dimer forms by a chemical substitution or external stimuli. Here, we report a pressure-induced collapse transition in the structurally related BaTi₂Pn₂O (Pn = As, Sb) at a transition pressure P_c of∼15 GPa. The Pn− Pn bond formation is related with Pn-p band filling, which is controlled by charge transfer from the Ti-3d band. At P_c, the Sb−Sb distance in BaTi₂Sb₂O shrinks due to bond formation, but interestingly, the Sb−Sb expands with increasing pressure above Pc. This expansion, which was not reported in ThCr₂Si₂-type compounds, may arise from heteroleptic coordination geometry around titanium, where a compression of the Ti−O bond plays a role. Electrical resistivity measurements of BaTi₂Sb₂Oup to 55 GPa revealed an increasing trend of the superconducting transition temperature with pressure. This study presents structure motifs that allow flexible bonding manipulation and property control with heteroleptic coordination geometry.