"We got outplayed all the way around," Arrieta said. "They did pretty much every facet of the game better than we did and that's why we lost."
Philadelphia remained three games behind Atlanta in the NL East after the Braves lost 1-0 to the New York Mets. The Phillies began the day one game out in the wild card race.
"We need to play better and the Braves need to not play as well," Arrieta said. "If those two things happen, we'll be fine. There's no need to panic but we need to stay locked in to the game."
Arrieta (9-9) allowed four runs and six hits in six-plus innings, his third straight losing decision.
Morales connected off Arrieta in the second, matching Jose Bautista (2014) for the Blue Jays' second-longest streak of games with a home run. Jose Cruz Jr. connected in a team-record six straight in 2001.
"I'm using my hands a little bit more," Morales said through a translator. "I wasn't using my back leg earlier in the season, I've been driving the ball with it and it's been going good so far."
McKinney homered for the second time in three games with a two-run drive to left in the third. A boy in the front row of the outfield seats caught the ball, then lifted his arms in celebration and exchanged a high five with a nearby fan.
Ryan Borucki (3-3) allowed two runs and seven hits in 6 1/3 innings as Toronto won its fourth straight.
"He's one of their best prospects for a reason," Phillies manager gave Kapler said of Borucki, who has won three of his past five starts.
Scott Kingery hit a solo home run for the Phillies but was also thrown out at home plate trying to score from second on Roman Quinn's one-out single in the second. Blue Jays outfielder Kevin Pillar got his seventh outfield assist.
"We did a lot of homework on the throwing in the outfield," Kapler said. "There's no question Pillar is a Gold Glove outfielder with a very good arm but we also know that there have been some throws that have been off line, so we're taking a bit of a risk there. Obviously it didn't work out in our favor."
Borucki gave up a run in the first on a sacrifice fly by catcher Wilson Ramos, then held the Phillies scoreless until Kingery's solo homer in the seventh.
"He pitched off the barrel," Philadelphia's Rhys Hoskins said. "We got some hits off him but he when he needed to make a pitch, he did."
Borucki left to a standing ovation and was replaced by Ryan Tepera, who got two outs. Tyler Clippard pitched the eighth and former Phillies closer Ken Giles finished for his 17th save in 17 opportunities, striking out Hoskins looking to strand runners at first and second.
END OF THE LINE
Blue Jays infielder Lourdes Gurriel Jr. was activated off the disabled list after missing 23 games because of a sprained left ankle. Gurriel entered with an 11-game streak of multihit games, the longest in the majors since Tony Perez did it in 1973. Manager John Gibbons started Gurriel in the leadoff spot to maximize his number of at bats. Gurriel grounded out in the first and struck out in the third before grounding an RBI single through the left side in the fifth. In his final shot at adding to his streak, Gurriel struck out against reliever Hector Neris in the seventh.
Philadelphia has lost 13 of its past 18 away from home. The Phillies are 28-37 on the road.
Phillies: Ramos returned to the lineup after missing three games because of a sore left wrist.
Blue Jays: To make room for Gurriel Jr., Toronto optioned INF Richard Urena to Triple-A. ... Gibbons said he told veteran OF Curtis Granderson to expect reduced playing time as the Blue Jays focus on their younger players.
Phillies RHP Nick Pivetta (7-10, 4.66) faces Blue Jays RHP Aaron Sanchez (3-5, 4.52) on Saturday afternoon. Pivetta is from Victoria, British Columbia, on Canada's West Coast. He is making his first career start north of the border. Sanchez will be activated off the 60-day DL to face the Phillies. He's been out since June 21 after injuring his right index finger when it got caught inside a falling suitcase.
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