ARLINGTON, Texas (AP) Francisco Liriano mostly cruised through the first three innings, looking to win his fifth straight start against Texas.
Then the Pittsburgh lefty gave up two homers to left-handed batters in the same game for the first time in his career - all in a matter of 13 pitches in the fourth inning.
Struggling sluggers Prince Fielder and Mitch Moreland homered during Texas' four-run frame, and the Rangers beat the Pittsburgh Pirates 6-2 Sunday for their eighth straight series victory at home.
Two of the four walks from Liriano (4-4) came before Moreland's homer, and he has nine walks in his past two starts.
''There's times when he gets in those situations that he seems to overthrow,'' manager Clint Hurdle said after the Pirates dropped the second of two interleague series so far this season. ''Two runaway walks to right-handers and two missed locations to left-handers. They both made us pay.''
Fielder ended a career-long homer drought at 34 games with his third of the season leading off the fourth inning. Moreland, who stopped a 1-for-27 skid with a home run Saturday, hit a three-run drive halfway up the upper deck in right field for his sixth, making it 4-2.
''You can't really focus on the numbers,'' Moreland said. ''That's for everybody else to worry about. You've got to go up there and continue to focus on your work and try not to base it on the results. That's what I've been trying to do.''
Texas starter Martin Perez (3-4), with a history of getting rattled in jams, escaped an inning with a runner at third and no outs for the second consecutive start. The left-hander gave up two runs in six innings and finished May with a 2.23 ERA.
Perez twice wiggled out of trouble after the Pirates put the first two runners on in an inning.
Francisco Cervelli's single in the fourth was followed by a double from Sean Rodriguez, but Perez got Matt Joyce and Chris Stewart on groundouts that kept the runners in place before throwing a called third strike to Jordy Mercer.
After Starling Marte's walk and another single from Cervelli starting the sixth, Rodriguez flied out, Joyce struck out and Stewart grounded out.
''When you see guys getting better in tough situations, that's what you can call a great pitcher,'' Cervelli said of Perez, who is 6-1 with a 2.15 ERA in his last 11 home starts. ''He's got a late sinker, and he was aggressive with every hitter.''
Liriano, who beat Perez 5-4 the last time he faced the Rangers in September 2013, gave up six hits and five runs with six strikeouts in six innings.
''With Fielder and Moreland, I tried to go up and in,'' Liriano said. ''I just left it in the middle.''
Texas closer Sam Dyson, pitching in a non-save situation for the second straight day, capped three scoreless innings from the bullpen with two strikeouts in the ninth.
The Rangers (29-21) moved a season-high eight games over .500 and took over first in the AL West, a half-game ahead of Seattle after the Mariners were swept by Minnesota.
David Freese's solo homer, his fourth of the season, gave the Pirates a 2-0 lead in the fourth.
WOE IS THE ROAD
Nine of the 10 homers Liriano has allowed this season have been on the road, and Pittsburgh just dropped a second straight road series to fall to 13-12 away from home. The Pirates had won three straight series, all on their longest homestand of the season, before coming to Texas.
Pirates: 2B Josh Harrison was out of the lineup for the second straight day as he battles an illness. He left in the sixth inning after starting Friday, a day after he didn't start but came off the bench.
Pirates: LHP Jeff Locke (3-3, 5.08 ERA) goes in the opener of a four-game series Monday night at Miami. Locke has won three of last four decisions and is 9-5 with a 3.31 ERA in 25 starts against NL East teams.
Rangers: LHP Derek Holland (3-4, 5.21 ERA) is to pitch on six days' rest in the opener of a three-game series at Cleveland. Holland is 0-3 in May but has a 2.84 ERA in his past two starts, when the Rangers scored just one run.