Bryce Harper makes his first visit to Fenway Park a memorable one by smashing a mammoth two-run home run to the deepest part of the park as part of a three-RBI night to power the Nats. (Jim Rogash/Getty Images)

A century’s worth of players have passed through Fenway Park, where history seeps through the emerald walls. Stephen Strasburg and Bryce Harper graced the cathedral for the first time on Friday night, and they did not dissolve into its annals. They made them richer, more complete: The old yard can say it bore witness to Strasburg and Harper at their unbridled beginning, the moment in time when the Washington Nationals became something fresh and different.

Two of the most arresting players in baseball spearheaded the Nationals’ assault on the Boston Red Sox in a 7-4 victory. Harper, the 19-year-old without an off switch, went 3 for 5 with a double, three RBI and a 420-foot, two-run home run. Strasburg, pitching on the two-year anniversary of his masterful debut, threw his first 100-mph fastball of the season, struck out 13 over six innings of four-hit ball and escaped a bases-loaded jam by throwing a 3-2 fastball with his 119th and final pitch.

Several other Nationals placed their stamp on the victory, too. Ian Desmond drilled a go-ahead, bases-loaded double, Danny Espinosa smoked two doubles and Xavier Nady made a once-in-a-season, homer-robbing catch. But the night belonged to Strasburg and Harper, the Nationals’ two former first overall picks, twin forces of nature.

Before the game, Harper chatted with David Ortiz, the slugger who blew him a kiss at last year’s All-Star Game. On the base paths, Dustin Pedroia told him, “Great job.” A fan sitting on top of the Green Monster yelled Harper’s name until he waved back. Harper absorbed everything, and then he grabbed the game by the throat.

“I’m 19 years old, so I still look at those guys as the guys I grew up watching,” Harper said. “It was pretty unbelievable to see that. Having an atmosphere like that, playing for the first time at Fenway, it was just an unbelievable experience.”

The place threw all it could at Strasburg. He began the sixth inning with 10 strikeouts, including seven of the previous nine batters. He struck out Pedroia twice and he whiffed leadoff hitter Daniel Nava three times — once on his magic-trick change-up, once with his curveball and once with his blazing fastball.

In total, Strasburg would induce 20 swing-and-misses, a new career high. He “kind of had a little bit of a breakthrough” with his breaking ball, he said, from a fascinating source. Strasburg wanted to make an adjustment with the pitch. He sought advice from Rick Ankiel, the outfielder who once was the hottest pitching prospect in baseball, before he lost the ability to throw a strike.

“I watched him growing up,” Strasburg said. “He had one of the best curveballs in the game, and he knew how to throw it and he knew how to use it to his advantage.”

With one out in the sixth inning, however, the Red Sox mounted a charge. Pedroia singled to left, Adrian Gonzalez doubled off the Green Monster and Ortiz drew a walk. Ross Detwiler heated up in the bullpen as Strasburg’s pitch count climbed past 100, toward his career high of 108 set earlier this season. The bases were loaded, the Nationals led, 7-2, and the Red Sox had their best chance to make it a game.

“There’s no way I’m hooking him with the bases loaded,” Manager Davey Johnson said. “I don’t care what his pitch count was. I was going to have to fight ownership if I let him go too long.”

Strasburg whiffed Jarrod Saltalamacchia lunging at a curveball in the dirt, pitch No. 113. Strasburg never glanced at the pitch-count display in center field.

“I knew it was up there,” Strasburg said. “But I had so much adrenaline being in Fenway for the first time, it didn’t really matter.”

After Kevin Youkilis ran the count full, Strasburg let loose a 96-mph fastball at the knees. Youkilis, know for his batting eye, spit on it.

Home plate umpire Doug Eddings pumped his fist: strike three, strikeout No. 13, matching the second-highest total of Strasburg’s career, one fewer than in his debut. Youkilis erupted and was thrown out of the game. Replays showed a borderline pitch. Strasburg walked off the mound.

“He’s like looking at a rainbow,” Boston Manager Bobby Valentine said of Strasburg before the game. “You don’t miss it. It’s a rather beautiful sight. He gets that pitching thing very well.”

The Nationals (33-23) could rest on their five-run lead, created in large part by Harper. He had come to Fenway once before, as an 11-year-old kid in 2004. Harper understood and embraced the nature of the park. “Just to step in the same batter’s box Ted Williams did, that’s pretty amazing,” he said before the game.

Then Harper left his own mark. In the top of the third, with Espinosa on first after a walk, Harper roped a low fastball into right-center field. Scott Podsednik cut if off before it reached the gap, but Harper didn’t care about that. He bolted for second and slid in headfirst with time to spare. Harper would score when Ryan Zimmerman lined a single to center.

In the next inning, Harper walked to the plate with Espinosa on third. Red Sox starter Felix Doubront tried to sneak an 0-1 fastball by Harper, and he unloaded with the full force of his vicious swing. The ball rocketed to center field, over the Red Sox’ bullpen, landing just to the right of the 420-foot mark on the fence.

Harper never saw where the ball landed. “I just run around the bases and let everybody else watch it,” he said. He sprinted so fast he reached third base before Espinosa reached the plate. The last three 19-year-old visitors to homer at Fenway were Robin Yount, Al Kaline and Mickey Mantle.

With an RBI single in his next at-bat, off left-handed specialist Rich Hill, Harper became the first teenager with three hits at Fenway since Ken Griffey Jr. in 1989.

“It seemed like Bobby was bringing in the left-handers for him all night,” Johnson said. “Didn’t seem to faze the kid.”

All three of Harper’s hits came off left-handers, the kind of pitcher that was supposed to give him trouble in the majors. He is 15 for 46 (.326) with two home runs against them. The league has not figured out what Harper cannot do. “They say he’s 19,” Valentine said. “It’s incredible.”

The crowd began filtering out in the late innings. They had seen enough of the home team. And they had seen another chapter added to Fenway’s history.