The San Diego Padres, though, have designs on extending their winning streak at PNC Park.
Looking to avoid an eighth consecutive defeat, the Pirates meet the Padres on Friday night for the first of three games.
Pittsburgh, which has had 18 straight losing seasons since its last playoff appearance, was a season-high seven games over .500 on July 19 and moved atop the NL Central five days later.
Now, they're trying not to get discouraged while taking a tumble down the division standings. A 7-6 loss to the Cubs on Thursday was the seventh straight for the third-place Pirates (54-56), who have dropped seven games behind front-running Milwaukee.
The Pirates may find it hard to reduce that deficit with the Padres coming to town. Pittsburgh has been outscored 37-15 during a six-game home losing streak to San Diego.
However, Pittsburgh took two of three from San Diego at Petco Park in May.
The Padres (48-64) begin a 10-game road trip following a 3-6 homestand that ended with Wednesday's 3-0 win over the Los Angeles Dodgers.
Despite being at the bottom of the NL West, San Diego is 25-28 on the road.
Coming off his first loss in nearly three months, Aaron Harang (9-3, 3.76 ERA) will take the mound for the Padres to begin this trip.
The right-hander surrendered six runs in 5 2-3 innings of Saturday's 10-6 defeat to Colorado. Harang had been 5-0 with a 2.99 ERA in 11 starts since losing to Pittsburgh on May 2.
He gave up a pair of two-run homers over five innings in that 4-3 loss, but Harang's 13 wins over the Pirates are tied for his most against any opponent.
Jeff Karstens (8-5, 2.49), who starts Friday for the Pirates, hasn't been able to come away with a win recently despite being consistently solid.
The right-hander has yielded three runs in each of his last three outings, posting an 0-1 record. He kept Philadelphia in check for seven innings Sunday in a 6-5, 10-inning loss.
The shortest of Karstens' 19 starts this year came May 3 in San Diego. He was reached for three runs and six hits in four innings but didn't get a decision in the Pirates' 6-5 loss.
The Padres' next error will be their 72nd of the season.
While that number might seem insignificant, it equals the total number of errors the team committed in all of 2010. The 72 total was the lowest in franchise history, and the Padres' .988 fielding percentage last season was the highest in club history.
Errors on defense -- both those that show up in the box score and mental mistakes -- are one reason behind the Padres' collapse this season.
Defense was a key to San Diego's success of 2010. Those Padres allowed only 32 unearned runs all season. This year the Padres have already given up 51 unearned runs and are on pace to give up 74 unearned runs and commit 104 errors.
Unearned runs have been a direct factor in eight Padres losses this season.
The Padres hope to shore up their defense this weekend when they play the reeling Pirates in Pittsburgh. The Pirates have dropped seven in a row, and they've lost nine of 10 since the controversial ending to their 19-inning defeat July 26 at Atlanta.
RHP Dustin Moseley, who had season-ending surgery on his left shoulder Wednesday, was victimized by a strange double this season. Not only did he have the second-lowest run support average in the National League, Moseley was hurt by 15 of the 51 unearned runs allowed by the Padres. Errors led directly to three of Moseley's losses. Moseley, who was 3-10 despite a 3.30 ERA, was also the losing pitcher five of the 16 times the Padres have been shut out.
LHP Josh Spence on Wednesday had his streak of retiring 14 straight batters snapped when he intentionally walked the first hitter he faced. He then retired the next two hitters he faced to get out of a bases-loaded jam without allowing a run. He has worked scoreless ball in 21 of his 22 games and has a 0.47 ERA.
RHP Chad Qualls has moved into the eighth-inning role since the trade of RHP Mike Adams to the Rangers. Qualls has allowed only two hits and no walks against six strikeouts over his last six appearances (5 1/3 innings).
LF Kyle Blanks is in a 1-for-23 slump and is batting .094 since being recalled from Class AAA Tucson on July 21. He has yet to get an extra-base hit or an RBI and has struck out 15 times in 32 at-bats.
LHP Joe Thatcher was activated from the disabled list after completing a rehab assignment with Class AAA Tucson. Thatcher has yet to pitch for the Padres this season due to a left shoulder strain that prompted surgery in May. He had a 1.23 ERA in eight appearances (7 1/3 innings) with Tucson. The Padres optioned OF Blake Tekotte to Class AA San Antonio. Tekotte went 6-for-24 (.250) in 12 games over two stints with San Diego.
By The Numbers: 5—Consecutive losses by the Padres to the Dodgers before Wednesday's win prevented a Los Angeles sweep at Petco Park.
Quote To Note: "Defense and situational hitting are two areas where we have fallen short of our 2010 levels." —Manager Bud Black, talking recently about the reasons behind the Padres struggles this year. (The loss an Adrian Gonzalez didn't help).
OF Chris Denorfia (strained right hamstring) left the game July 31 and didn't play Aug. 1-3.
RF Will Venable (back spasms) was a late scratch July 29 and didn't play July 30-Aug. 1. He appeared as a reserve Aug. 2-3.
LHP Joe Thatcher (left shoulder strain) went on the 15-day disabled list retroactive to March 22. He had surgery May 2, and he was transferred to the 60-day DL on May 4. Thatcher began a rehab assignment with Class A Lake Elsinore on July 17, and he moved his rehab to Class AAA Tucson on July 19. He was activated Aug. 4.
C Nick Hundley (bone chips in right elbow) went on the 15-day disabled list retroactive to July 6. He had arthroscopic surgery July 8. He began a rehab assignment with Class AA San Antonio on Aug. 3, and he is expected to be activated by mid-August.
RF Brad Hawpe (strained right middle finger) went on the 15-day disabled list retroactive to June 19.
RHP Dustin Moseley (left shoulder strain) went on the 15-day disabled list retroactive to July 27. He had season-ending surgery Aug. 3.
LHP Clayton Richard (left shoulder strain) went on the 15-day disabled list July 5. He underwent an arthroscopic debridement procedure July 29 to clean and smooth the glenoid labrum, biceps tendon and rotator cuff. He is out for the season.