TORONTO -- Caleb Joseph's new upright stance and growing confidence have done wonders for the Orioles rookie catcher, transforming untapped potential into unexpected power.

While Joseph might have never received the opportunity to be a starter in a major league pennant race had Matt Wieters not needed season-ending elbow surgery — or had Joseph not worked tirelessly in the minors to improve behind the plate — he has given the Orioles a tremendous boost with his bat in his past four starts.

Joseph's two-run homer in the fourth inning -- the club's only offense against Toronto Blue Jays left-hander J.A. Happ -- led the Orioles to a 2-1 win in Thursday night's series finale in front of an announced 34,676 at Rogers Centre.

Joseph, 28, became just the second Orioles rookie to homer in four consecutive games -- Jay Gibbons also did it in 2001 -- and he is just the third catcher in club history to accomplish the feat, joining Ramon Hernandez (2006) and Gus Triandos (1959).

“This time of the year, runs are at such a premium,” Orioles manager Buck Showalter said. “Players are worn down from playing all year. It's August. These are the dog days. … Caleb was able to ambush the one [mistake Happ made]. Boy, he didn't make many. He was impressive. That was not fun to watch, but impressive.”

With the victory, the Orioles (65-49) took two of three games here in Toronto and claimed their season-high sixth consecutive series win, as well as their fourth straight on the road.

The first-place Orioles headed back to Baltimore for a six-game homestand against the St, Louis Cardinals and the New York Yankees with a five-game lead in the American League East over the Blue Jays and the Yankees.

“These are big games,” Joseph said. “They’re right behind us, and when you’re playing head-to-head games, leads can swing really quick. They’re a great team. They’re going to be on our tails pretty much the whole year. They do a lot of things right.

"We had to come in and take care of business, and taking two of three is gratifying because they’re coming after us hard. There’s a few teams behind them two that was coming pretty quick, so we’ve got to continue to keep playing solid baseball.”

The Orioles have taken control of the division through some tough travels on the road. They've been successful while heading out west for a 10-game road trip last month, playing a rescheduled game in Washington on Monday and racing sunrise to Toronto that night.

The Orioles are now 20-8 on the road since May 31, and their 35 road wins are the most by any AL team this season.

They've won the first two series this season in Toronto, which used to be a House of Horrors for them. Their final trip here, which will be the final three games of the regular season in late September, could hold tremendous importance if these teams remain close together atop the division.

“We've just got to keep grinding and make the games we play matter,” Showalter said. “It's a given that good teams like Toronto and New York and Tampa, everybody in our division, they're going to do their thing. We're going to have to earn it and, with the schedule we play, we'll have to.”

Joseph, who needed 33 games to hit his first three major league homers, has launched longballs in each of his past four games. Joseph credits an adjustment in his stance -- hitting coach Jim Presley told Joseph to stand taller in the box and swing down at the ball in order to create more backspin -- for his sudden power surge.

“It’s been a huge factor,” Joseph said of the adjustments. “I’ve gotten into a couple weeks here where I really feel like an improvement’s been made and I’m just trying to continue that and kind of getting back to what I did last year [at Double-A Bowie].

"I had a good year last year hitting. You get up here and struggle early on and you search to put the ball in play with hard contact, so you may tinker with a few things. … It's been going well so far. Keep working on it every day.”

On Thursday, he launched a 2-0, 93-mph fastball from Happ into the first row of the left-field seats to break a scoreless tie in the fourth inning. Joseph's homer, which followed J.J. Hardy's leadoff ground-rule double, was the Orioles' only hit with runners in scoring position in eight opportunities off Happ.

Over his last 11 games, Joseph -- who entered this year having played just 22 games above Double-A during his first six professional seasons -- is hitting .342 while playing solid defense and throwing out 48.5 percent of base runners.

“I think [his defense] actually takes a little weight off him offensively,” Showalter said. “Caleb, he’s not going to take his lack of experience, or his so-so slow start as an excuse -- and his good catching -- as an excuse not to hit. You need everybody in our league to do something.”

Happ (8-6) held the Orioles to just five hits and recorded a career-high 12 strikeouts. After Joseph's homer, he retired the final 14 Orioles batters he faced.

Orioles right-hander Miguel Gonzalez battled with his pitch count, but he still recorded a quality start, allowing one run and four hits in six innings.

Gonzalez (6-6), who needed 79 pitches to get through his first four innings, made only one mistake: a solo homer to No. 9 hitter Anthony Gose to open the fifth.

Gonzalez worked his way out of trouble throughout the night against the Blue Jays (61-55). He stranded two runners in the third inning after issuing back-to-back, two-out walks. He left two runners in scoring position in the fourth after inducing a flyout from Ryan Goins.