The conversion of rookie lefthander Charlie Furbush from reliever to starter is a work in progress.
Furbush (1-1) was acquired in a trade with Detroit on July 30. For the Tigers, he was a reliever, but the Mariners think he can be a starter.
Furbush wasn't bad in his first start for Seattle on Aug. 3, allowing one run and two hits in five innings to get the win in a 7-4 victory over Oakland.
This time, things didn't go nearly as well against the free-swinging Rangers.
"Right now, it's hard to take any positives out," Furbush said. "I know this is going to be a process, getting back into a starting mode. I'm not in any way satisfied with the results tonight. It's something you've got to stick in the back pocket and keep working at it."
Furbush got in trouble against the Rangers when he leaned too heavily on breaking pitches at the expense of his fastball.
"You've got to like his arm, you've got to like his stuff, but being comfortable and being familiar with those type situations, that's the kind of hump you've got to get over," manager Eric Wedge said.
The Mariners started the night with a .228 team batting average, lowest in the majors, and they managed only two runs and five hits off Rangers starter Matt Harrison (10-8).
Harrison had six strikeouts and no walks in 104-degree heat, and Nelson Cruz backed him with a homer.
The Rangers scored twice in the second against Furbush with the help of the Mariners' second error of the night.
Cruz snapped an 0 for 15 slide when he led off the second with a homer to left, and Mike Napoli reached second on Mariners third baseman Adam Kennedy's fielding error.
Napoli went to third on a groundout and scored on Moreland's single.
When the Rangers loaded the bases with nobody out in the fifth on two walks and a single, Wedge brought in ex-Ranger Jamie Wright from the bullpen.
The Rangers kept up the pressure in the inning with RBI singles by Napoli and Torrealba, and a bases-loaded walk to Moreland for a 7-2 pad.
In the sixth, Cruz's RBI double and Napoli's run-scoring single off Tom Wilhelmsen made it 9-2.
The Mariners, 2-9 against the Rangers this season, have lost 22 of their last 28 games overall.
NOTES: Seattle 1B Justin Smoak missed his fifth straight game with a left thumb injury. Smoak took early batting practice on Monday and was confident he could return to the lineup soon. ... Rangers RHP Alexi Ogando was back with the team after spending the weekend in the Dominican Republic for the birth of his child. Ogando will be activated off the paternity list to make Tuesday night's scheduled start against Seattle. The Mariners will start RHP Michael Pineda, the AL rookie leader in innings pitched (130), strikeouts (133) and opponent batting average (.205). ... In the fourth, Texas' Josh Hamilton and Cruz tried to stretch singles into doubles, but they were thrown out at second by OFs Trayvon Robinson and Ichiro Suzuki.