Dodgers’ Adrian Gonzalez has been mostly ineffective at the plate this month

Adrian Gonzalez illuminated his ongoing dilemma at the plate with two swings in the ninth inning of a 6-1 loss to the Pirates on Saturday. He has skidded through June, with his on-base-plus-slugging percentage down to .709, his worst production since he was a 23-year-old rookie with Texas in 2005.

Gonzalez demonstrated the issues at hand in the ninth. Facing reliever A.J. Schugel, Gonzalez received a 2-0 fastball at the thighs. He chopped a groundball, foul, down the first base line. Then he saw another fastball at the thighs. He swung late and hit a lazy flyball into left.

This is the ineffective combination Manager Dave Roberts sees from the player the Dodgers hoped could still be an offensive cornerstone: Too many groundballs to the pull side, too many flyballs to the opposite field. Roberts suggested the combination stemmed from Gonzalez trying to go the other way to beat the shifts that clog the right side of the field during his at-bats.

Roberts said Gonzalez, a 34-year-old with chronic neck and back issues, has insisted he is healthy. He insisted this diminished version of Gonzalez “isn’t the new normal.”

“He’s always been streaky,” Roberts said. “I have no doubt that he’ll come out of it and slug the way he can.”

Tepesch out, Taylor in

The Dodgers designated pitcher Nick Tepesch for assignment on Saturday afternoon, ending his tenure with the team less than 24 hours after he gave up five runs in four innings of a start against the Pirates. The team recalled multipurpose infielder Chris Taylor.

The Dodgers still need a fifth starter for the rotation. Roberts was unwilling to reveal any of the candidates to take the ball on Wednesday in Milwaukee. But neither Hyun-Jin Ryu nor Brandon McCarthy will be considered for the assignment, he said.

Taylor, 25, was acquired in a trade with Seattle in exchange for pitcher Zach Lee last Sunday. He hit .240 in 256 plate appearances with the Mariners from 2014 to 2016. Roberts indicated he planned to start Taylor on Monday against the Pirates, though he was “not sure where.”

To make room for Tepesch on Friday, the team designated outfielder Will Venable for assignment. Venable accepted an outright assignment to triple-A Oklahoma City on Saturday.

andy.mccullough@latimes.com

Twitter: @McCulloughTimes