PHOENIX -- Cliff Pennington singled home Miguel Montero with one out in the last of the ninth inning, and the Arizona Diamondbacks overcame a 14-strikeout performance by Yu Darvish for a 5-4 victory over the Texas Rangers, completing a doubleheader sweep at Chase Field on Monday.
Pennington's single was his second walk-off hit of the year, the Diamondbacks' fourth walk-off victory and their 11th win in their last at-bat. Pennington had a game-winning hit a 16-inning victory over the St. Louis Cardinals on April 3.
Montero doubled to open the ninth off Jason Frasor (0-1) before Robbie Ross entered to face pinch hitter Martin Prado. After an intentional walk, Pennington grounded a ball inside the bag at first.
Rangers right-hander Darvish gave up seven hits and four runs in 7 2/3 innings. He tied a career high with his 14 strikeouts and didn't walk a batter. Darvish left after throwing 116 pitches, 83 strikes. He leads the majors with 105 strikeouts.
Didi Gregorius had two hits, including a two-run home run with one out in the eighth inning to tie the game at 4 after Wil Nieves opened with a pinch single. Darvish had retired 18 of the previous 20 with 11 strikeouts before Nieves batted. Gregorius was the only Arizona starter who did not strike out against Darvish.
Adrian Belte had two hits and scored twice, and Lance Berkman singled, walked twice and scored twice for Texas (32-20).
The Rangers have lost three in a row for the first time this season and were swept in a doubleheader for the first time since May 3, 2007.
Brad Ziegler (1-2) got the last out in the top of the ninth for the D-backs (30-22), who have won four of their last five games.
Darvish is the first pitcher since Arizona's Randy Johnson in 2004 to have three games of at least 14 strikeouts in a season. Darvish had not given up a run after the sixth inning this season until Gregorius' homer in the eighth.
Arizona left-hander Tyler Skaggs (1-0) struck out a career-high nine in six scoreless innings of a 5-3 victory in the first game, when Prado tied a franchise record with a first-inning single that gave him seven hits in as many at-bats.
Skaggs was recalled from Triple-A Reno for the start and as the designated "26th player" for the doubleheader was to be returned to the minors Tuesday.
In the second game, Arizona had a 2-0 lead after Darvish's first four pitches. Gerardo Parra singled to center, Gregorius tripled into the right field corner and Eric Chavez hit a sacrifice fly on a 1-0 pitch.
The Rangers scored on A.J. Pierzynski's sacrifice fly in the second inning and on an infield error in the fourth before taking a 4-2 lead in the sixth.
Berkman walked before singles by Adrian Beltre and Pierzysnki scored the first run in the sixth. Beltre scored on a fielder's choice groundout.
NOTES: Prado, originally scheduled to start both games of the doubleheader, was held out of the start of the second game after fouling a ball off the inside of his left leg in the fifth inning of the opener. ... Berkman started the second game at first base, the first time he has played in the field this season. He has started 42 games at designated hitter, and he pinch-hit in the first game Monday. ... Parra left the second game in the top of the fifth inning. He appeared to turn his left ankle when he struck out on a Darvish breaking ball in the fourth inning. ... In a strange bit of scheduling, Arizona and Texas will have Tuesday off before playing a two-game series in Rangers Ballpark on Wednesday and Thursday. The games are the only four meetings between the teams this season.