The Dodgers have won 12 of their last 14 meetings with the Pirates heading into Monday night's opener of a four-game set at PNC Park.
Los Angeles (62-53) is one game behind San Francisco for the division lead. Pittsburgh (64-50) holds the second wild-card spot, with the Dodgers and St. Louis 2 1/2 games back.
The Dodgers swept a three-game home set from the Pirates from April 10-12, but they come to Pittsburgh with a different look now that Hanley Ramirez has joined the team.
Ramirez, acquired July 25 from Miami, enjoyed a big weekend series in his return to South Beach as he went 6 for 13 with five RBIs to help Los Angeles win two of three. The three-time All-Star has 17 RBIs in 16 games with the Dodgers.
"His swing is great and if he just takes his hits, he's going to drive in a ton of runs, but he's going to hit more home runs, too," manager Don Mattingly said. "Hanley can hit. He sees the ball early. He's a talented cat."
Matt Kemp went 6 for 14 over the weekend and is hitting .439 with 12 RBIs over his last 14 contests. He's batted .447 in his last 10 games against Pittsburgh, including nine Dodger wins.
The Pirates avoided a fourth straight loss and a three-game sweep by San Diego with Sunday's 11-5 victory. Pittsburgh rallied from a five-run deficit after two innings, as Clint Barmes' first career grand slam highlighted a nine-run fourth inning.
"We're pretty good," manager Clint Hurdle told the Pirates' official website. "We're not perfect. We'll confuse you. We'll probably anger you from time to time, but we're going to let it all hang out. We're going to play hard, and they found a way to dig one out of the dirt today."
Neil Walker, who went 0 for 8 in the first series against the Dodgers, matched a career high by going 5 for 5 on Sunday to break out of a 3-for-19 slump.
The Pirates have yielded first-inning runs in six straight games and hope that Jeff Karstens (4-2, 3.77 ERA) can get them off to a better start Monday. Karstens gave up three runs over six innings Tuesday and did not get a decision in a 10-4 defeat to Arizona, increasing his home ERA to 1.33.
The right-hander, 2-0 in four outings at PNC Park this year, fell to 0-3 with a 4.94 ERA in five starts against the Dodgers after yielding three runs over five innings in a 3-2 loss April 12. Kemp (3 for 9) and James Loney (4 for 12) have enjoyed success against him.
Karstens will be matched up with another San Diego-born right-hander in Aaron Harang (7-7, 3.80), who owns more victories at PNC Park than at any other visiting ballpark - going 8-3 in 11 starts despite a 4.46 ERA.
Harang lost his second straight outing Tuesday by surrendering three runs in six innings of a 3-1 home defeat to Colorado.
Andrew McCutchen, leading the majors with a .362 average, is 2 for 9 against Harang. Barmes is 4 for 9 with a homer.