Colon (16-6) scattered seven hits, allowed one walk and struck out seven in the efficient 108-pitch performance.
Grant Balfour yielded a walk in the ninth but finished up with his 38th save for the American League West-leading Athletics, who reeled off a fourth straight win and clinched their three-game series against Texas.
Brandon Moss provided the game's only run with a first-inning RBI double.
Rangers starter Yu Darvish (12-9) took the hard-luck loss, surrendering just the one run on four hits over seven innings. He walked one and struck out 10.
Slumping Texas, which dropped a fifth straight, came into the contest holding the first AL wild card spot with a 2 1/2-game cushion for a post-season berth.