OKLAHOMA CITY — Kevin Durant spent Saturday afternoon doing what he does on every rough end of a back-to-back road set: napping in his hotel room. When he arrived around 5:40 p.m. CT at Chesapeake Energy Arena, his first time back here since he signed with the Warriors in July, the former face of the Oklahoma City Thunder was reminded just how different this game is. During Durant's pregame presser, at least 50 reporters gathered, recorders and cameras in hand. Some held signs welcoming back the community's adopted son; others hoisted posters with old tweets in which Durant had pledged his allegiance to this small-market franchise. [...] nothing could prepare him for this: walking into Chesapeake Energy Arena's visiting locker room for the first time; seeing the support staffers he had come to know as friends; wearing another team's jersey in the building he had once thought would always be his home.