Martin bashed a three-run homer and added a run-scoring single while Elvis Andrus and Adrian Beltre combined to go 6-for-9 with four RBI as the American League West-leading Rangers rolled to a third straight win over the Mariners.
Beltre provided a two-run shot and Mitch Moreland added a solo blast for Texas, which came into the contest with a 2 1/2-game lead over second-place Oakland.
The Rangers racked up a seventh victory in nine games overall.
Martin Perez (8-3) claimed a fifth win in five starts, becoming the first Texas rookie to do so. The left-hander allowed two runs on five hits over six innings, walking three and striking out two.
Seattle's Felix Hernandez (12-8) was tagged for nine runs (eight earned) on 11 hits in a three-inning effort.
Dustin Ackley went 2-for-4 with a solo homer and two RBI for the Mariners.