They've had pretty good success when facing the division's fourth-place team as well.
The Pirates have won four straight against the Cincinnati Reds, who look to add a fourth club to the list of Central contenders when they open a three-game set at PNC Park on Monday night.
Pittsburgh (49-44) was 1 1/2 games behind both Milwaukee and St. Louis on July 3, but it's made things even tighter in the upper half of the NL Central by taking advantage of the division's bottom-feeders.
The Pirates won two of three against both the woeful Astros and the Chicago Cubs prior to the All-Star break, and did the same to begin the second half in Houston.
The Pirates - a division-best 22-13 against Central foes - trail the front-running Brewers by a half-game, but they're percentage points ahead of the Cardinals for second place thanks to Cincinnati.
The Reds (47-48) had lost three series in a row heading into Sunday's finale against St. Louis, but won 3-1 to take two of three.
Cincinnati is just 3 1/2 games out of first despite not winning consecutive games since a three-game sweep of the Dodgers from June 13-15.
The Reds are 15-10 against the Cardinals and Brewers, but they've had a tougher time figuring out the Pirates. Pittsburgh has won five of six in the 2011 series, all in Cincinnati.
None of those wins came against Dontrelle Willis (0-0, 3.00 ERA), however. Willis will make his second start in a Cincinnati uniform after giving up two runs over six innings July 10 at Milwaukee, where Cordero's blown save cost him a win.
James McDonald (5-4, 4.42) counters for the Pirates after going four straight outings without a decision, including July 8 against the Cubs when he gave up three runs over 5 2-3 innings.
He's had two contrasting outings this year against the Reds. McDonald was shelled for seven runs over 4 1-3 innings in an 11-2 loss April 16, but held Cincinnati to a Jay Bruce solo homer over 6 2-3 innings in a 5-3 win May 19.
Homer Bailey didn't have it in the bullpen before his start Sunday against St. Louis, but he found enough of whatever he needed on the mound.
The Cincinnati right-hander turned in 7 1/3 solid innings to help set the stage for a 3-1 Reds victory that lifted them to their first series win since taking two of three at Tampa Bay June 27-29 and their first at home since winning two of three against the Cubs June 6-8.
"It was just one of those things," said Bailey, who improved to 4-4 and lowered his earned-run average from 4.13 to 3.74 by allowing only Lance Berkman's solo homer in the second inning.
"I showed up at the ballpark not feeling great, but we won, so everything's great. Warming up before the game, I felt like I had nothing. I was all over the place, I was thinking I might not get past the second inning, but it worked out."
Bailey, Cincinnati's No. 1 pick and the seventh overall selection in the June 2004 draft, displayed the grit of a veteran in adjusting to his discomfort and getting the most out of what he did have on hand, catcher Ryan Hanigan said.
"He got a little frustrated," said Hanigan, whose single through a drawn-in infield, drove in Miguel Cairo with the run that snapped a 1-1 tie in the seventh inning. "I told him to go back to his checkpoints. I said, 'We're not reinventing the wheel here.' I told him to loosen up, that he didn't have to throw every pitch on a dime. He has good enough stuff that all he has to do is change speeds in the zone. He wasn't trusting his fastball. That's why we went with a lot of breaking stuff early. It was one of those days where you don't have it in the bullpen, but you can't let it bother you too much."
The win was Bailey's first in six starts since May 16. He missed the first month of the season and another month from late May to late June with shoulder problems.
"He did a great job," Hanigan said. "The key was getting him through the fifth, sixth and seventh innings. That's where he's been getting hurt. That's when you've got to execute."
LHP Dontrelle Willis is scheduled to continue his comeback from control problems when he makes his second start since being called up by the Reds on Monday night at Pittsburgh. Willis was the victim of a blown save in his Cincinnati debut July 10 at Milwaukee, leaving with a 3-2 lead after six innings.
LHP Matt Maloney threw two scoreless innings Saturday for the Reds' rookie-level Arizona League team in his first rehab appearance since fracturing a rib during a sneeze in late May. Maloney was placed on the 15-day disabled list on May 26 and transferred to the 60-day DL on May 29.
RHP Jose Arredondo threw a bullpen session Sunday at 80 percent, according to MLB.com. He has been out since July 7 due to a strained right forearm.
Saturday's 4-1 loss to St. Louis extended to 24 the number of consecutive games the Reds had played without winning at least two straight. Cincinnati was 9-15 in that span, but hadn't dropped more than four games out of first place.
According to Elias Sports Bureau, Friday's game was the third of the season in the majors in which a team started with a leadoff homer and ended with a walk-off homer. CF Chris Heisey led off the game with a homer, and 2B Brandon Phillips ended it with a two-run shot. The Nationals did it on June 16, also against St. Louis, and the Angels victimized Seattle on July 8.
INF Miguel Cairo couldn't have picked a better time for his first triple since 2009, when he was with Philadelphia. Cairo, after taking a strike while asking for time out, tripled into the right-center field gap with one out in the seventh inning, setting up C Ryan Hanigan's go-ahead single.
The Reds improved to 5-1 against St. Louis in Cincinnati and 7-5 overall while increasing their number of wins against Central Division teams to a division-leading 28. After their three-game series at Pittsburgh, they open a stretch of 10 consecutive games against non-Central teams.
By The Numbers: 5—Hits by the Reds in 29 at-bats with runners in scoring position while taking two of three against St. Louis over the weekend.
Quote To Note: "It feels great. That's in the past. We're starting the second half, and we're starting the right way, taking two out of three from St. Louis. Tough times are going to happen sooner or later, but you've got to deal with it and come out of it. You've got to be able to put it behind you and move forward. I made some good pitches to get some good hitters out." —RHP Francisco Cordero, on snapping a stretch of three consecutive blown save opportunities with a perfect ninth inning against the Cardinals' Albert Pujols, Matt Holliday and Lance Berkman on Sunday.
RHP Jose Arredondo (strained right forearm) went on the 15-day disabled list retroactive to July 7. He threw off a mound July 17.
LHP Matt Maloney (cracked rib) went on the 15-day disabled list retroactive to May 24, and he was transferred to the 60-day DL on May 29. He began a rehab assignment with the Reds' affiliate in the rookie-level Arizona League on July 16.
RHP Jared Burton (right shoulder inflammation) went on the 15-day disabled list retroactive to March 29. He suffered a setback in early April, and he was transferred to the 60-day DL on April 18. He underwent arthroscopic surgery April 22.