The 24-year-old Byron from Charlotte, North Carolina, led a race-high 212 of 403 and fended off Joey Logano during an overtime shootout to repeat as a Cup winner at the Paperclip-shaped short track.
The three-time Daytona 500 champion from Chesterfield, Virginia, fended off Kevin Harvick in the final five laps to notch a breakthrough victory at his home track.
The Mitchell, Indiana, native became the 200th different competitor to achieve a win in NASCAR's premier series following his first career victory in the desert state.
The Tucson, Arizona, native made a late two-tire pit strategy work to his advantage after fending off teammate Larson in overtime to capture first victory at Vegas.