The Rockies’ early-season express came to a halt Sunday afternoon at Seattle’s T-Mobile Park in a 5-3 loss to the Mariners. The Rockies — who saw their three-game winning streak end and saw their record slip to 11-4 — were derailed by Mariners left-hander Justus Sheffield and undone by their own mistakes. Colorado right-hander German Marquez, so good in his first three starts this season, was not as sharp Sunday, giving up five runs (two earned) over seven innings.