Latos spotted the Mariners an early 3-1 lead but played a key role in helping erase the advantage in the fourth inning.
With the doubling Jack Hannahan aboard and two outs in the frame, Seattle elected to intentionally walk Ryan Hanigan to get to Latos. But the pitcher crossed up the strategy by belting a pitch into the right-center field gap, tying the score.
He then came in to score the go-ahead run on Shin-Soo Choo's RBI single.
Latos (8-2) allowed four runs on six hits, walking four to go along with his 11 strikeouts as the Reds evened their three-game interleague series.
Mariners starter Jeremy Bonderman (1-3) was tagged for six runs on seven hits over five frames.
Kyle Seager went 2-for-3 with a two-run homer and three RBI for Seattle.