The first week of the Washington Nationals season has been an exercise in sputtering starts and stops. The Nationals have played seven games in nine days, and the two off days may have provided some extra rest, but also seemed to prevent the team’s revamped lineup from establishing a rhythm. The offense, expected to be a strength of a team many view as World Series contenders, had yet to show its full capabilities. That changed Tuesday as the Nationals’ bats broke out in an 8-7 win over the Chicago White Sox in an early interleague matchup, the first of a stretch of 25 games in 26 days. Home runs? The Nats hit four, including two from Adam LaRoche in his return from a sore back. On-base percentage? New leadoff hitter Denard Span reached base three times and scored twice. “There’s not really any easy spot in the lineup,” Jayson Werth said. Werth’s third home run broke a sixth-inning tie, showing that his surgically repaired left wrist is perfectly fine after his power numbers ebbed last season. He added an important insurance run with an RBI single in the seventh. LaRoche awoke from a 0-for-15 start to his season in rousing fashion with two shots over the fence. The offensive explosion was just enough to withstand the runs surrendered by Tyler Clippard and Rafael Soriano. With the score knotted at 2-2 in the sixth inning, Werth strode to the plate against White Sox starter Jake Peavy, who baffled the Nationals for much of the first five innings In the fourth inning, Werth hit a ball off Peavy the furthest possible without leaving the stadium, 400 feet to dead center, for an out. Peavy fielded a coaching visit to the mound before facing Werth again. It did no good. Werth hammered the first pitch Peavy threw him — a low, 90-mph fastball — into the left field seats for a two-run home run. An inning later, leading by only a run and with pinch hitter Steve Lombardozzi and Span on base because of walks, Werth stroked a single through the left side of the infield to give the Nats a 7-5 lead. Through seven games hitting second in the lineup, Werth has drawn no walks. “His wrist is feeling good and he’s being more aggressive,” Manager Davey Johnson said. “I like that. He’ll get his walks, I’m not worried about that.”