Abreu, given the night off, was batting an even .400 this season with runners in scoring position, second in the American League to the Rays' Jason Bartlett.
"We had our best hitter [Abreu] up there and came up short," Napoli said. "The guy [Hill] made a great play. Juan hit the ball hard. It might have been a little different if we had the bases loaded there when I came up. It didn't happen."
If Rivera's bullet had escaped Hill's grasp, they'd have gone to the bottom of the ninth tied.
"He's at double-play depth, and that ball was scorched," Angels manager Mike Scioscia said. "He got it with a full-tilt dive."
Rzepczynski, who turns 24 in eight days, held the potent Angels offense in check for 6 1/3 innings as the Jays ended their five-game losing streak.
Quiet except for doubles by Rivera and Kendry Morales producing a run in the seventh, the Angels stirred in the ninth against Brandon League. Singles by Torii Hunter and Vladimir Guerrero preceded the shot by Rivera, who'd lined out to third leaving two men in scoring position in the first inning.
"Juan hit bullets to third and second with runners in scoring position," Scioscia said. "It happens."
After producing 65 runs in eight games, the Angels have been held to 10 in their past three outings and seven in 18 innings in two successive losses.
Not since Aug. 4-5, in Chicago against the White Sox, had the Angels dropped back-to-back games.
A 6-foot-3 lefty, Rzepczynski is about as local as it gets. He was born in Yorba Linda, Calif., about 20 minutes from Angel Stadium, and schooled at UC Riverside, another 20 minutes east.
Familiarity might not have bred contempt, but it certainly didn't hurt his confidence, judging by the way Rzepczynski deadened Angels bats that have been leading the Majors in runs scored and batting average.
"He threw strikes and got us to hit ground balls," Napoli said. "He threw the ball well. Hats off to him. It's tough facing somebody for the first time. You've got to see some pitches."
Not as efficient as Rzepczynski, who claimed his second win in five decisions, was Sean O'Sullivan.
The Angels' 21-year-old right-hander got cuffed around for four first-inning runs, starting with Hill's 29th homer, and departed after walking the leadoff man in the second.
Matt Palmer restored order, holding the Jays to a Vernon Wells solo homer over the next four innings, and Jose Arredondo worked three superb innings, yielding one hit and two walks while striking out five.
"The bullpen did a great job," Scioscia said. "What Matty Palmer and Arredondo did was terrific to get us in position to come back in the ninth."
O'Sullivan's problem was fundamental in slipping to 3-2.
"Getting strike one," Napoli said. "He couldn't do that tonight."
"It's not hard to pinpoint," said O'Sullivan, who has been in a downward spiral his past three starts after a brilliant Major League debut in San Francisco and a 3-0 start. "I'm falling behind. I'm not throwing strike one. The game's so much easier when you're ahead in the count."
Rzepczynski repeatedly jumped ahead in the count. After Rivera's bullet ended the first inning, the lefty found his rhythm and took complete control.
"The first inning, he looked like he was a little nervous about who he was facing over there," Jays manager Cito Gaston said. "I think maybe after that first inning, he kind of thought, 'Well, I can get these guys out, too,' and he did a great job. Outstanding."
Rzepczynski yielded nothing more than a Rivera single into the seventh, when he coolly gloved Guerrero's leadoff liner at his belt.
"He was as billed," Scioscia said of Rzepczynski. "You see a guy with good life on his fastball, good movement, who gets his slider under swings. He moved the ball around and threw a lot of strikes."
After Rivera followed Guerrero's lineout with a ringing double to left, Rzepczynski departed to an ovation. Former UCLA athlete Josh Roenicke, a right-hander acquired from the Reds at the July 31 non-waiver Trade Deadline, yielded a double to Morales, who assumed the club lead with his 82nd RBI.
The nephew of Angels bench coach Ron Roenicke retired Kendrick to end the inning.
It was left to another young Jays pitcher, Janssen, to notch his first save -- courtesy of Hill.