In the 11th off of Bobby LaFromboise (0-1), Kole Calhoun singled with one out and was nearly doubled off first when Erick Aybar lined out to center. He got back in time, though, and Aybar roped a pitch off the wall in left-center as Calhoun came home for the winning run.
"I was just looking to get on base, he threw me a slider and I was able to put the barrel on it," said Iannetta.
Andrew Romine went 3-for-4 and drove in the other two runs for the Angels, who have won five of their last six games. Cory Rasmus (1-1) got his first career win for pitching a 1-2-3 top of the 11th.
Michael Saunders brought in both runs for the Mariners, who have lost five of their last six.
"It was a good ballgame, both teams weren't able to get that final big hit until the end," said Seattle manager Eric Wedge. "We were one hit away."
The game stayed scoreless until the seventh inning when the Mariners went on top. With one out, Nick Franklin doubled and Mike Zunino followed with a walk. Two batters later, Dustin Ackley's single loaded the bases and Saunders hit a single to center for a 2-0 lead.
The Angels, though, came back in the bottom of the frame. Mark Trumbo reached on a bad throw from Kyle Seager and Kole Calhoun followed with a walk. Aybar's sac bunt moved both runners up a base and Romine singled them both home to tie the game.
Erasmo Ramirez gave up two runs -- both unearned -- on six hits and a walk in six-plus innings for Seattle. Matt Shoemaker gave up two hits and two walks in five innings for the Angels.
It was LaFromboise's first career decision ... The Angels have won 10 of the 17 games against the Mariners this season ... Seattle was just 2-for-14 with runners in scoring position and stranded 10, while LA was 1-for-9 with RISP and left nine.
09/21 03:02:45 ET