The six-foot-one, 211-pound right-hander pitched seven solid innings and was buoyed by three Toronto home runs as the Blue Jays defeated Detroit 5-1 before a sun-drenched Rogers Centre gathering of 41,832 for just their second home series victory over the Tigers since 2006.
"Henderson's seven innings certainly set the tone," said Toronto manager John Farrell. "He was strong, he was consistent with his changeup and he threw some good sliders.
"He trusts his fastball a lot and he should when you have that kind of sink and can throw in the mid-90s consistently."
Toronto improved to 3-2 on its current homestand, which will end with the series finale against Detroit on Sunday.
Alvarez (7-7) surrendered a run on five hits over seven innings with four strikeouts and two walks for the win. He had some help in the first inning when third baseman Brett Lawrie of Langley, B.C., made a nice leaping catch of a one-out Quintin Berry line drive before left-fielder Travis Snider's outstanding diving snag of a two-out drive from Prince Fielder with one on.
"It always helps having guys making plays for you," Alvarez said through an interpreter. "After those two plays I got pumped up and it helped me get through the game and pitch well."
The 22-year-old Venezuelan registered his team-high 11th quality start of the season and went at least seven innings for the eighth time this season.
"He had a fastball that was more electric than we anticipated," said Detroit right-fielder Brennan Boesch.
Alvarez was aided by four Toronto homers in his last win, a 15-7 decision over Boston on July 22 that saw him allow seven runs over 5 2-3 innings. He was sharper Saturday and was against the beneficiary of long-ball support, including Colby Rasmus' 18th homer, a two-run shot in the seventh that ended Detroit starter Anibal Sanchez's day.
"I was really, really impressed," Tigers manager Jim Leyland said of Alvarez. "He's got a real live arm."
Detroit (53-48) suffered its third straight loss and fourth in five games after a five-game win streak briefly moved the Tigers atop the AL Central. Sanchez (5-8) was acquired from Miami last week with infielder Omar Infante but surrendered five runs and eight hits through six innings in his Tigers' debut.
"The last few days we haven't done enough to win games, plain and simple," Leyland said. "We either made a couple of mistakes pitching or we haven't got the big hit or I haven't pulled the right strings."
Left-hander J.A Harp worked the final two innings for Toronto (51-49).
Toronto outhit Detroit 10-5 with Edwin Encarnacion and Yunel Escobar also belting solo homers. Rasmus finished 2-for-3 with three RBIs in his first stint as the DH with Anthony Gose starting in centre field.
"It definitely was weird in the beginning," Rasmus said of not playing in the field. "But I just stayed focused on the game and watched him pitch and what he was trying to do with the hitters so it would give me a better chance when I got up there."
Alvarez got himself into a jam in the sixth by issuing one-out walks to Miguel Cabrera and Fielder but ended the threat by getting Delmon Young and Boesch to both fly out. Escobar then led off the bottom of the inning with a solo homer, his seventh of the season to give Toronto a 3-1 advantage.
Encarnacion's solo shot, his 28th of the season to lead off the fourth, put Toronto ahead 2-1
Detroit made it 1-1 in the top of the inning on Boesch's two-out double that scored Young, who had singled.
Rasmus opened the scoring in the third, his sacrifice fly bringing home Gose, who had singled.
Notes: Toronto slugger Jose Bautista swung a bat before the game for the first time since suffered a left wrist injury in New York on July 16. Bautista is currently on the 15-day disabled list and eligible to come off Aug. 1, although Farrell figures Bautista will need additional time to fully recover. ... With his first-inning double, Lawrie extended his hit streak to seven straight games. ... Toronto left-hander Brett Cecil (2-3, 5.82 earned-run average) takes on Detroit right-hander Doug Fister (4-7, 4.03 ERA) on Sunday. Left-hander Ricky Romero (8-7, 5.75 ERA) will open Toronto's road series at Seattle on Monday night . ... Detroit is in the midst of a nine-game road trip that will conclude with a three-game series in Boston starting Monday night. ... Prior to Saturday's game, Toronto had scored a major league-leading 496 runs.