The numbers are stark. Throughout his career, Daniel Nava has been a far better hitter against right-handed pitchers than against lefties. Still, John Farrell played a hunch. So, even though the Red Sox opened Fenway Park today by facing Orioles left-hander Wei-Yin Chen, Nava was in the starting lineup, playing left field in place of scuffling rookie sensation Jackie Bradley Jr. And on cue, he delivered. After Chen muted the Red Sox for six innings, they began to stir in the seventh. Dustin Pedroia reached on an infield single, strapping Mike Napoli launched a double off the wall in left-center, and up stepped Nava with a chance to break a scoreless stalemate and finally give the lead to starter Clay Buchholz. Nava took the first pitch and fouled off the second, both fastballs. Then, the switch-hitter crushed Chen’s third straight fastball over the Green Monster to fuel a 3-1 victory in the first-place Red Sox’ homecoming. “We just felt like, against another very good lefthander, it was a chance to get Nava’s righthanded bat in there,” Farrell said before the game. “He puts up a consistent at-bat. I think numbers bear it out that he’s had more success left-handed, but just in general he’s been a confident offensive player right now and we want that additional right-handed bat in the lineup.” Indeed, Nava is a .265 hitter with a .776 on-base plus slugging percentage in 383 career plate appearances against right-handed pitchers. Against lefties, he has only a .191 average and .621 OPS. But Nava also was 4-for-10 in his first three games, including a homer in Sunday’s 13-0 thrashing of the Blue Jays.