Iwamura had two of Tampa Bay's 12 hits.
Carl Crawford and Delmon Young hit RBI singles, Elijah Dukes hit a solo homer, Ty Wigginton hit a sacrifice fly and the Devil Rays capitalized on three Yankees errors, three wild pitches and a passed ball.
Ruddy Lugo (1-0) got the win, throwing 2/3 inning in relief, and Al Reyes recorded his first save of the season by retiring the side in order in the ninth.
The losing pitcher was reliever Luis Vizcaino (1-1).
The game-time temperature was 38 degrees and snow flurries became heavier in the late innings.
Notable deaths of 2014 [PHOTOS]