Jones fought Toney, Hopkins who were both easily as good as Hagler if not better, and Griffin was technically way better than Hagler.. Also Hagler wasn’t always relentless in the Hagler-Leonard fight he thought he could box with Leonard, and lost the first three rounds, and also against Duran he tried to box him. Against Hearns he was lucky it ended when it did because they both couldn’t go 12 rounds at that pace. Nobody came close to outworking prime Jones so there is no evidence he would have been worn down by the smaller, not as strong Hagler.