Tommy Hunter could not protect a one-run lead in the sixth and Guerra (1-3) took the loss in the seventh.
The loss was the Phils' second in a row after winning four straight. They are 9-11 at the one-third mark of the 60-game season.
The Phils are 1-4 in seven-inning games.
Toronto has won four in a row.
Rookie right-hander Spencer Howard pitched well. He didn't stick around long in the seven-inning game, but he pitched well. He allowed five hits and just one run in 3⅔ innings and left with a one-run lead.
Howard featured mostly his power fastball; forty-nine of his 67 pitches were heaters. The pitch averaged 95.1 mph and topped out at 97. He got eight swings and misses on the pitch, which was very encouraging.
In his previous outing, Howard gave up a home run to Robinson Cano of the Mets on a hanging curveball. Howard completely ditched the pitch in this outing. He complemented the fastball with nine sliders and nine changeups.
Manager Joe Girardi got Howard out of the game with two outs, two men on base and a run in in the fourth inning. Blake Parker came in and got out of the inning.
Mixed bag in the bullpen
Parker and Jose Alvarez combined to get through the fifth inning and preserve the Phillies' one-run lead.
Parker has pitched well with four scoreless appearances since his recall.
Alvarez got a huge out to end the fifth, but it came at a price. He was struck in the groin with a 105-mph line drive off the bat of Gurriel. Alvarez courageously retrieved the ball and made the play at first before falling to the ground in pain. He had to be carted off the field but managed to wave to teammates. More on his condition as it becomes available.
Veteran Tommy Hunter could not protect the one-run lead in the bottom of the sixth. He allowed a leadoff single to Billy McKinney, who moved up on a bunt and a ground ball. McKinney then scored the tying run on a two-out double by Cavan Biggio. Biggio hit a 2-1 cutter over Harper's head in right.
Hunter has made eight appearances. Five have been scoreless. He has allowed a total of five runs in three others.
The Phillies' bullpen, of course, is the worst in the majors. It entered the game with an 8.11 ERA.
Vince Velasquez will pitch against right-hander Trent Thornton (0-0, 2.25) in the second game.
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