The first three home runs of Brady House’s career weren’t just pulled. They were pulled straight down the left field line. Good swings, all of them. But mirror images, pretty much, in each case.

That made Friday night’s homer during the Nationals’ 6-5 win over the Pirates significant. Because it didn’t look like the other homers. This time, House drove the ball to right-center.

Leading off the bottom of the sixth, with his team trailing 3-0 at the time, House jumped on a first-pitch slider from Pittsburgh starter Mitch Keller and drove it 402 feet the other way, the ball clearing the out-of-town scoreboard in right-center for a solo shot that ignited the whole lineup.

“I saw it, and I just tried to be on time that at-bat,” the rookie third baseman said. “Just happened to go out, so I’m happy about it.”

It’s been a tough rookie season in some ways for House, who was called up in June with a reputation as one of the organization’s top power prospects. He slugged .519, connecting for 13 homers, in 283 plate appearances at Triple-A Rochester. But the power has dried up in the majors: Even with Friday’s blast, he’s slugging a mere .344 with four homers in 238 plate appearances at the highest level.

Interim manager Miguel Cairo is quick to point out how young House is: He turned 22 days before his promotion to the big leagues. There’s plenty of time for him to figure things out and blossom into the kind of hitter he’s supposed to be.

More concerning than the lack of power, though, has been House’s free-swinging approach. He currently sports a 67-to-6 strikeout-to-walk ratio that simply won’t cut it in the long run. He swings at the first pitch of an at-bat 53.4 percent of the time, way higher than the MLB average of 30.1 percent.

“He’s aggressive. He’s going to swing,” Cairo said. “What we want him to do is hit it in the strike zone. Don’t let the pitcher dictate where you want to swing.”

So, what happened on House’s home run swing Friday night? He got a first-pitch slider over the plate, jumped on it and got to trot around the bases in celebration.

For what it’s worth, all four of House’s major league homers have come on breaking balls. He’s still seeking his first one off a fastball.

But overall, there have been signs of improvement. Over his last 17 games, House is batting .268 and slugging .446, with a .718 OPS. He still has drawn only one walk against 20 strikeouts, but when he does make contact, he’s hitting the ball with more authority.

“He’s looked a lot more settled, swinging at the right stuff,” teammate James Wood said after Friday’s homer sparked the Nationals’ rally. “He has tons of juice. That was a sweet swing, and it was big for us, just getting us started.”