This study considers a decentralized supply chain where a manufacturer supplies a newsvendor-type item to a retailer who sells the item in two different marketplaces. The manufacturer lowers the two wholesale prices and offers a buyback commitment to operate the chain as a centralized one. The buyback contract, however, is assumed to only accept one of the two marketplaces’ unsold products, which not only allows the manufacturer to collect the near marketplace’s returns if facing a same demand uncertainty but also determines which marketplace is advantageous to implement the return practice if facing two different demand uncertainties. The objective is to create a win-win situation via negotiating the two wholesale prices and the buyback price. The contributions are twofold. If the two marketplaces face a same demand uncertainty, our contract includes the existing complete-return contract as a special case. If the two marketplaces face two different demand uncertainties, our contract will determine which one of the two marketplaces should implement the return practice.