ARLINGTON, Texas -- Viewing the Orioles' starting pitching the past three days, it's not hard to see why Baltimore has the best record in the major leagues since June 2012.
Chris Tillman took his turn Sunday and exceeded the standard set the previous two games.
Tillman pitched a strong eight-plus innings, helping the Orioles complete a three-game sweep of the Texas Rangers with a 4-2 victory. It was Baltimore's sixth victory in the past seven games.
Baltimore's starting pitchers went 3-0 with a 1.71 ERA in the three-game series. Wei-Yin Chen, Miguel Gonzalez and Tillman combined to strike out 13 Rangers hitters and walk only five.
Tillman (12-3) scattered six hits and three walks while striking out seven, winning for the 10th time in his last 11 decisions. His only loss in that time was to the New York Yankees on July 6.
Since June 2012, only Detroit Tigers right-hander Max Scherzer has a better winning percentage than Tillman, who has gone 20-6 in that span.
"I had a little of everything going today," Tillman said. "I had everything going tonight. I tried to stay aggressive with the fastball, and the curveball felt good.
"Starting pitching is very important. We stated a little slow, but hopefully we can pick it up here in the second half."
In the past eight games, Orioles pitchers have made seven quality starts.
Tillman gave up a solo home run to Adrian Beltre in the bottom of the ninth on the last of his 117 pitches.
Brian Matusz got the first out of the ninth inning, and Darren O'Day recorded the final two outs to register his second save of the season.
"Anytime you come into a ballpark like this with a club like this and you get them all, it's important," Tillman said of the sweep. "Hopefully, we'll keep it rolling."
The Orioles have also been hitting the ball well.
Matt Wieters, Brian Roberts and J.J. Hardy each had two hits and an RBI. Manny Machado added a run-scoring hit, while Nate McLouth recorded two hits for the Orioles, who move on to Kansas City for a three-game set after moving 13 games over .500.
Wieters was 6-for-10 in the series with a double, a home run, two RBIs and four runs.
The Rangers are in a midseason free fall, losing for the seventh time in eight games.
Texas starter Martin Perez (3-3) gave up four runs on nine hits in 6 1/3 innings.
Rangers second baseman Ian Kinsler went 2-for-4. A baserunning error possibly cost Texas a run in the fifth when Kinsler was caught in a rundown after his run-scoring hit. David Murphy made a move to score from third but was thrown out.
In another costly mistake, Texas shortstop Elvis Andrus booted what likely would have been a 6-4-3 double play in the Orioles' two-run second.
"Very uncharacteristic baseball," Rangers manager Ron Washington said. "Plays we take pride in making we just haven't made. We'll just keep grinding."
The Orioles missed a chance to break the game open early, but they still scored twice in the second inning.
Chris Davis led off with a fly ball that turned into a double when Murphy, the Rangers left fielder, lost the ball in the sun. Davis scored on Wieters' single to center, which was followed by Hardy's infield single. After Danny Valencia reached on Andrus' error, Roberts singled home Wieters, leaving the bases loaded with no outs.
However, Perez settled down and struck out McLouth and Machado before inducing a groundout by Nick Markakis to get out of the inning.
"We get a sun ball, then a routine double play that gets away," Washington said. "We had opportunities."
Two-out doubles by Wieters and Hardy led to the Orioles' third run in the third.
Orioles manager Buck Showalter said, "Good pitching allows you to overcome leaving the bases loaded and not scoring."
NOTES: Baltimore improved to 16-8 against American League West teams this season. ... Wieters has hit safely in six of seven games against Texas, batting .370 with four RBIs. ... The temperature at Rangers Ballpark in Arlington read 93 degrees at first pitch. ... The Orioles improved to a major-league-best 73-58 on the road since the start of the 2012 season. ... Washington said RHP Alexi Ogando (shoulder inflammation) would make his return Tuesday against the Yankees, barring something unforeseen between now and then.