"It's something I was thinking about for a long time," said Johnson, who got the celebratory pie to the face from Adam Jones and Robert Andino before sharing a special moment with his father in the tunnel leading up to the clubhouse. "[To] get my first win and have him here. And the way those days worked out, 23 years to the day, it's just special. It's all I can really say about it. It means a lot to me."
Battery mate Matt Wieters -- fresh off catching Tuesday's 14-inning win -- ensured that the rookie would get some run support. Wieters, who made it clear he wanted to be behind the plate for Johnson's debut, tied a career high with five RBIs as the surging O's improved to nine games over .500 for the first time since June 26.
Johnson's gem helped the Orioles extend a five-game winning streak -- tying their season high -- and kept the club in a three-way tie for the first Wild Card spot and just 4 1/2 games back of the American League East-leading Yankees.
"I think it's a little bit of a morale or karma or whatever that our guys know, whether you're on the roster, off the roster, whatever, you come in and you're wearing our colors and you present yourself as the best option, we're going to figure out a way to take you," said manager Buck Showalter, who came close to sending Johnson out for the seventh inning just to send him off with an ovation.
"He deserved an opportunity, and tonight he took advantage of it."
If he was nervous, Johnson -- who had just two innings of relief in the big leagues prior to taking the hill -- didn't show it. Instead, the Baltimore native came out firing. All 12 of Johnson's first-inning pitches were called strikes as the young righty struck out the side and managed to get out of a bases-loaded, one-out jam in the second.
"It's a lot of anticipation of the start," said Wieters, who was impressed with Johnson's composure. "I'm sure you can get a lot of anxiety built up with the situation, pitching for the team that your dad was so great for. He handled himself real well tonight with everything, considering."
The O's bats afforded Johnson a cushion from the get-go courtesy of Wieters' two-out, two-run double. Coming off a career-high three-extra base-hit night, including a pair of homers, Wieters doubled twice and kept Johnson, who surrendered only a two-run homer, on track.
The Orioles scored a pair of third-inning runs off former teammate Kevin Millwood and a three-run fourth chased the veteran from the game. In that frame, Mark Reynolds blasted Millwood's 2-2 offering -- sending it into straightaway center field for his first homer since July 16 -- and red-hot Nick Markakis followed with a two-run homer. Since moving to the leadoff spot after coming off the disabled list, Markakis is batting .360 with six doubles, a triple, four homers, 21 runs scored and 11 RBIs in 26 games.
But the night belonged to Johnson, who got a rousing ovation from the crowd upon being shown on the JumboTron after his exit and was greeted by approximately 40 family members and friends after the game. Using a fastball that topped out at 93 mph and routinely sat in the upper 80s, Johnson allowed five hits and a pair of walks in the 97-pitch outing.
"It was a sneaky 88, that's what it was," Mariners catcher John Jaso said. "It was riding up in the zone pretty good.
"We got ourselves out a lot and that's what will happen when you start swinging at balls out of the zone, trying to do too much instead of letting the pitcher come to you."
Orioles Troy Patton tossed a 1-2-3 seventh inning while reliever Miguel Socolovich, who was recalled prior to the game, tossed two scoreless innings to cap the Orioles' eighth win in their last 10 games.