Dodgers’ momentum stalls again with 6-3 loss to Pirates

PITTSBURGH — This can’t continue, not if the Dodgers have any intention of playing baseball in October.

They can’t afford to follow every win with a loss, as was the case yet again Sunday, when Zack Greinke and the offense supporting him stumbled in a 6-3 defeat by the Pittsburgh Pirates at PNC Park.

Whatever momentum the Dodgers had from their victory the previous night vanished, and they went into their day off with a 29-39 record. Every other team in the National League West, even the fourth-place San Diego Padres, has a record better than .500.

BOX SCORE: Pittsburgh 6, Dodgers 3

Everyone in the clubhouse seems to agree on what needs to happen: The Dodgers have to put together a winning streak. They haven’t won more than two consecutive games since the first week of the season, when they swept the Pirates in a three-game series at Dodger Stadium.

“We haven’t just got real hot,” Greinke said. “I can’t tell you why. It just hasn’t happened.”

Starting pitching is one reason the Dodgers believe such a streak could start at any time. They thought they could be on the verge of one when they won a game started by Clayton Kershaw on Saturday night, with Greinke and Hyun-Jin Ryu scheduled to start the next two games.

But Greinke (3-2) was charged with five runs and eight hits in five innings, inflating his earned-run average to 4.22. He gave up a two-run double to Garrett Jones in the first inning and a three-run home run to Pedro Alvarez in the fifth, sending the Dodgers tumbling to their second defeat in Pittsburgh in three days.

“Some big situations came up and I made bad pitches,” Greinke said.

This appeared to be a significant step back for Greinke, whose season was interrupted by an operation to repair a fractured collarbone. He’d looked sharp in his previous two starts, pitching seven innings in each and giving up a total of two runs and six hits.

But those two starts were at home, where Greinke is 3-0 with a 2.12 ERA. He is 0-2 with a 7.85 ERA in four road starts. The uneven splits are normal from Greinke, who is 58-30 in his career at home and 36-50 on the road.

As was the case when asked why the Dodgers rarely won more than one or two games at a time, Greinke said he didn’t know why he had so much trouble winning games after spending the night in a hotel room.

“It’s been going on long enough,” Greinke said.

Manager Don Mattingly remained in search of positive signs. He found one in Andre Ethier, who was six for 12 in the three games in Pittsburgh. He was two for four Sunday and drove in two runs.

Yasiel Puig was three for four with a stolen base and scored a run. Hanley Ramirez was held out of the lineup as a precaution to protect his recently healed left hamstring. Mattingly expressed hope that the offense could pick up once Ramirez was cleared to play every day.

Former UCLA star Gerrit Cole, a Pirates rookie pitching in his second major league game, improved to 2-0, limiting the Dodgers to three runs and seven hits in 52/3 innings. He struck out one.

dylan.hernandez@latimes.com

Twitter: @dylanohernandez