ATLANTA -- Derek Lowe says the Atlanta Braves are showing their true form in May.
For Lowe against the Pittsburgh Pirates, it's a form he has maintained throughout his career.
David Ross and Chipper Jones each drove in three runs, Lowe remained undefeated in his career against Pittsburgh and the surging Atlanta Braves beat the Pirates 7-3 on Friday night.
The Braves had 13 hits, including three by Ross, while improving to 8-2 in their last 10 games.
"We're starting to play like we feel we should have all year," Lowe said.
The Braves are 17-8 in May following a 9-14 April that included a nine-game losing streak. The Braves (26-22), a season-high four games over .500, remained 1½ games behind first-place Philadelphia in the NL East.
The Pirates have lost three straight and seven of nine.
Lowe (7-4) gave up only one run on four hits and one walk in seven innings. He improved to 9-0 in nine career starts against Pittsburgh. Lowe is 4-2 in May, including two wins over the Pirates in a span of seven days.
Lowe said he has no explanation for his success against Pittsburgh.
"I have no idea," he said. "It's completely different guys. It's just like why do you struggle against certain teams."
Braves manager Bobby Cox said Lowe was "mixing his pitches really well, trusting them a little bit more."
Lowe threw only 87 pitches in his seven innings.
"Some guys just feel comfortable against certain teams," said Pittsburgh's Neil Walker, who had two doubles and drove in a run. "He had his stuff working tonight. He did what he had to do to get the victory."
Ross and Jones each had bases-loaded hits. Ross had a three-run double in the first and Jones knocked Zach Duke (3-5) out of the game with a two-run single in the sixth.
The start of the game was delayed 1 hour, 21 minutes by rain and lightning. Many fans sat under umbrellas and ponchos as rain continued through the first five innings. With the Braves needing only two outs for the win, the rain returned in the ninth inning, forcing another delay of 1:10.
Following the delay, Jonny Venters struck out Jeff Clement and Bobby Crosby to end the game.
Ross, starting in back-to-back games for only the second time this season, helped the Braves take a 4-0 lead in the first inning.
Ross filled in for the second straight game for Brian McCann, who was held out a strained right quadriceps.
Duke gave up a season-high 12 hits and seven runs in 5 1/3 innings. He allowed only one run in each of his last two starts.
"It was a little bit of bad luck and a little bit of erratic command," Duke said, adding he couldn't blame his poor first inning on the rain delay, which came after each starting pitcher had completed his pregame warmups.
"I have a job to do, regardless," Duke said. "I've dealt with it before."
Pittsburgh manager John Russell said, "It didn't seem to bother Lowe very much."
"[Duke] settled in after the first inning. He threw well after that. He gave up too many runs in the first. That was extremely difficult to overcome."
Pinch-hitter Andy LaRoche and Walker had run-scoring doubles off Eric O'Flaherty in the eighth inning.
After Lowe threw only five pitches while retiring the Pirates in order in the top of the first inning, Duke threw 27 pitches while giving up four runs in the bottom of the inning.
Martin Prado, who had three hits, led off with a single and scored on a single by Troy Glaus. Ross doubled past Lastings Milledge to the left-field wall to drive in three runs.
Lowe, hitting only .067, doubled to lead off the second inning and scored on Jones' single to right for a 5-0 lead.
The Pirates held out shortstop Ronny Cedeno due to tightness in his lower back.
The Pirates placed RHP Charlie Morton on the 15-day disabled list with right shoulder fatigue. RHP Steven Jackson, recalled from Triple-A Indianapolis, relieved Duke in the sixth. ... LaRoche was held out of the starting lineup for the sixth time in seven games with a sore back. ... Lowe's double was his first extra-base hit since Aug. 20, 2006 when he hit a double for the Dodgers at San Francisco. ... Ross also started in consecutive games on May 6-7. ... RHP Todd Redmond pitched a no-hitter for Triple-A Gwinnett Braves in a 4-0 win at Louisville.