Cooling apparatuses and coolant-cooled electronic assemblies are provided which include a thermal transfer structure configured to couple to an electronics card which operatively inserts into an electronic system. The thermal transfer structure includes a clamping structure movable between opened and clamped positions. A coolant-cooled structure, which is associated with the electronic system within which the electronics card is operatively inserted, resides between the electronics card and, at least partially, the clamping structure with insertion of the electronics card into the electronic system. The opened position of the clamping structure facilitates docking of the electronics card within the electronic system with the coolant-cooled structure between the card and, at least partially, the clamping structure, and movement of the clamping structure to the clamped position facilitates clamping of the thermal transfer structure to the coolant-cooled structure, and thermal conduction of heat from the card to the coolant-cooled structure.