Mariners end July with fewest runs scored in MLB. Time to worry?

This Seattle Mariners offense scored runs so frugally through July that a night like this to end the month only seemed a fitting end to capture their month-long swoon.

The Mariners’ 5-2 loss to the Houston Astros on Tuesday night at Safeco Field secured their place as the worst run-producing offense of any team in the majors for the month of July.

That’s a problem. The Mariners christened two of their new bullpen arms for the first time with right-hander Sam Tuivailala and Zach Duke making their Mariners debuts, but relief arms aren’t much help when the Mariners only managed to muster runs in the fourth and sixth innings.

They were trailing 3-2 in the ninth when Duke, who was one of three…