Moreland homered for the fifth time in his last five starts and Harrell won in his Texas debut as the Rangers beat the Kansas City Royals 5-3 to finish a sweep of the four-game series.
After having their 10-game division lead shrink to 2 1/2 games last Wednesday, the Rangers have pushed the advantage back up to six games.
Harrell (3-2) gave up three runs and four hits -- including solo home runs to Eric Hosmer and Drew Butera -- in six innings. The 31-year-old right-hander was acquired from Atlanta last Wednesday to help the Rangers' injury-riddled starting rotation. Sam Dyson earned his 22nd save.
"More than anything else, what we saw this weekend is when we get quality starts . we have an opportunity to utilize our bullpen the way we need to," Texas manager Jeff Banister said.
The Rangers received quality starts in three of the four series games. They received quality starts in only three of their previous 21 games in July.
"This team's already on a roll," Harrell said. "My job is to come in and get people out and keep us in the game."
Kansas City hit just 2 for 25 with runners in scoring position during the series. The defending World Series champions went 7-19 in July, their worst month since recording the same record in July 2012.
"We take probably the last couple of weeks and try to forget that," Eric Hosmer said. "Times are just rough."
Moreland's two-run homer was his 18th this season, the last five coming within 16 at-bats. Nomar Mazara also homered against the Royals, who have allowed an AL-high 141 homers this season.
Since Prince Fielder was lost for the balance of the season to another neck injury, Moreland has hit .366 with six homers. In the series, Moreland hit .615 with four homers.
"I'm trying to go up there and have good at-bats," Moreland said. "It definitely worked out well for me this series."
Dillon Gee (3-5) gave up four runs and seven hits over six innings in his longest and most effective start of the season. He had a 6.43 ERA in six previous starts.
Banister sat young power-hitter Joey Gallo, a left-handed hitter, against the right-handed Gee. Gallo is 1-for-14 with nine strikeouts since being recalled from Triple-A Round Rock last week.
"This guy has minor league power pedigree that we're willing to be patient with," Banister said.
"We're still winning, and that's the best part about it," Gallo said. "It just takes time."
The temperature was 96 degrees at first pitch and reached 99. ... Gee played collegiately at Texas-Arlington and makes his off-season home in nearby Fort Worth. ... Banister also sat CF Ian Desmond and SS Elvis Andrus ahead of Monday's travel day. . Adrian Beltre got his 2,873rd career hit, tying him with Babe Ruth for 43rd place all time.
Kansas City placed closer Wade Davis on the DL (flexor strain). LHP Matt Strahm was brought up from Double-A Northwest Arkansas and made his major league debut. He faced three batters and allowed one earned run. ... Rangers RF Shin-Soo Choo (back) did rehab work Sunday for the second straight day and reported no discomfort. He hopes to be ready when eligible for re-activation on Thursday.
Royals: LHP Danny Duffy (6-1) will start the series opener at Tampa Bay on Monday. Duffy has five wins and four no-decisions in his last nine starts, most recently losing on June 6.
Rangers: RHP Yu Darvish (2-2) will make his seventh start since starting his season in late May following Tommy John surgery when the Rangers open a series at Baltimore on Tuesday. Both losses have come since returning from the disabled list on July 16 following shoulder discomfort. He could reach 100 pitches for the first time this season.
This story has been corrected to show the Royals were 2 for 25 with runners in scoring position in the series.
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