Jackson challenged hitters on the inside portion of the plate and threw a few on the outside corner, too. He mixed in a really good slider and some offspeed stuff.
Mainly, though, Jackson won his ninth game of the season with a dominant fastball and an offense that threw eight runs on the board in the first four innings.
Welcome to life with the Washington Nationals.
This season has been a coming-out party for an entire franchise, for a roster that has been constructed carefully and smartly by general manager Mike Rizzo and for a beautiful ballpark a mile south of the U.S. Capitol.
The Nats are the whole package, from the wily manager (Davey Johnson) to the veteran leadership (Adam LaRoche) to an assortment of some of baseball's best talent (Ryan Zimmerman, Bryce Harper, Ian Desmond, etc.).
These Nationals are also a reminder that baseball hasn't changed all that much the last century. Everything they do begins with the fact that they've collected a bunch of gifted, young, power arms.
Stephen Strasburg has dominated news coverage of the club, and rightfully so. His fastball has been the best in the Major Leagues this season, averaging 95.7 mph and helping establish him as one of the premier pitchers in the game.
(This column isn't about the club's decision to shut Strasburg down next week, but it's absolutely the right thing to do. He's 24 years old and two seasons removed from Tommy John surgery. To overwork Strasburg would be to put a potentially Hall of Fame career at risk. But that topic was worn out months ago.)
Strasburg has been so good he has made it easy to overlook his four teammates. All of them throw hard. All of them use the fastball aggressively. All of them make hitters uncomfortable.
Best of all, three of them -- Jordan Zimmermann, Gio Gonzalez and Ross Detwiler -- are 26 years old. Jackson is the oldest member of the rotation at 28.
Rizzo drafted Strasburg, Zimmermann and Detwiler. He used other Draft picks to acquire Gonzalez from the A's last winter. Jackson is the only free-agent signee.
"We feel good about these guys," Rizzo said. "We're all fired up that they've come together at such an early age. We feel they're going to be with us for a long time, and they kind of thrive off each other. They're an extremely close-knit group. They're competitive in all phases, not only pitching. If you ever watch a BP session with them, it's serious competition."
Because they're so close in age, they feed off one another, compete with one another and ultimately challenge one another.
"We definitely attack hitters," Zimmermann said. "If one guy goes out and goes six, the other guy is going to try and match that or do a little better. It's a snowball effect. We're always picking each other's brains. It helps to know what each other is thinking."
They're all good enough to command their fastball and to win with it and it alone. The Nats are No. 1 in the Majors Leagues with 93.2 mph average fastball velocity, according to Fangraphs.com.
The Nationals also throw the second-highest percentage of fastballs in baseball (64.7 percent), second only to the D-backs, according to Fangraphs.
Strasburg (95.7), Zimmermann (93.8), Jackson (93.4) and Gonzalez (93.2) have four of the top 11 fastball velocities in the majors.
Six years ago when Rizzo took over baseball's worst farm system, he had a fairly simple goal.
"The grand plan was to build a young, swing-and-miss power rotation from within," he said Tuesday afternoon.
Rizzo needed five years to transform Washington from the bottom of Baseball America's annual rankings of farm systems to the top. He acquired an array of talent across the board, establishing the Nationals has a team positioned to compete for years to come.
But Rizzo's basic philosophy was that power pitching is still the best way to build a winning baseball team. Now the Nats have the best record in the Majors at 83-52. Their rotation has the best ERA in the Majors and the most quality starts. They've also generated the second-highest percentage of swings and misses (23.7 percent).
"I've handled a lot of young pitchers over my career," Johnson said. "This group has actually gotten closer to pitching up to their potential and know more about themselves quicker than a high percentage of other young pitchers I've had. They're getting where they need to be quicker."
The Nationals are way more than pitching. They're a very good defensive team and are the National League's third-highest scoring team since the All-Star break. In ways large and small, they're a complete club.
"That's kind of the way we mapped this thing out, and it's come together pretty well," Rizzo said.
Richard Justice is a columnist for MLB.com. Read his blog, Justice4U. This story was not subject to the approval of Major League Baseball or its clubs.