Belarus in 2004-2014 is a subsidised client. Ukraine after 2004 Orange Revolution is a contested borderland. They are different mechanisms inside the same imperial political system.
Russian dominance can produce short term client-state rents (Russia sells very cheap crude to Belarus, Belarus sells world price refined products to world market), but it tends to trap countries in dependency, weak modernization, and political subordination. When a country tries to leave the orbit, the coercive part of the system appears. Ukraine had it's gas price dramatically increased, then supply interrupted, among other pressure.
