Alonso and Robinson Canó doubled in the first inning off Trevor Bauer. Wilson Ramos was hit by a pitch and Conforto launched a three-run homer, his 31st.
Eight of New York’s nine hits went for extra bases.
The Reds scored in the first on Aristides Aquino’s sacrifice fly, the first of 13 consecutive batters Stroman retired before Kyle Farmer hit his ninth homer, a two-out solo shot in the fifth.
Stroman allowed three hits and two runs with three walks and two strikeouts while lasting 4 2/3 innings, one out short of qualifying for the win.
Edwin Diaz pitched a scoreless seventh, Seth Lugo gave up Tucker Barnhart’s 10thhomer leading off the eighth and Justin Wilson pitched the ninth for his fourth save after getting the loss on Saturday.
Bauer (11-13), in his 10th start since being acquired from Cleveland at the trade deadline, didn’t walk anybody, but he hit two batters in seven innings. He gave up six hits and five runs with eight strikeouts.
Reds: RHP Sonny Gray (11-7) starts Tuesday at home vs. Milwaukee. His first strikeout will be his 200th of the season, extending his career high.