Pedro Baez falls off the mound and Dodgers lose to Giants 6-4

Reporting from SAN FRANCISCO —  In the dugout, a pained expression haunted the face of manager Dave Roberts. The moment did not defy belief, not if you’ve cataloged the ineptitude of this Dodgers team in this season’s first month. But it came close: In the seventh inning of a 6-4 loss to San Francisco, Pedro Baez balked in a run by falling off the mound.

Seriously. This happened.

“That’s a freak thing,” Roberts said. “Very unexpected.”

To Baez’s credit, he did not crumple to the ground. But he did drive in the go-ahead run when his cleats tripped across the dirt in the center of AT&T Park’s diamond. His gaffe created a fitting visual for the 2018 Dodgers. In trying to recover from last November’s agony, the Dodgers (11-13) have performed like a club uninterested in playing this October.

They fell on Friday for the third game in a row. They squandered a quality outing from Hyun-Jin Ryu, who struck out seven in 52/3 innings and delivered a two-run double in the fourth inning. Roberts pulled Ryu after 89 pitches and watched his bullpen implode. Tony Cingrani and Baez combined to allow four runs in the seventh. The offense had no answer to the assorted gas cans in San Francisco’s bullpen.

Baez played a role in a Dodgers loss for the second time this week. He failed to protect a deadlock in a game against the Miami Marlins, a team assembled for the express purpose of losing. Baez was pitching for inexplicable reasons in that game, as Roberts chose him over Kenley Jansen in the ninth inning.

Roberts had fewer options on Friday, as Cingrani melted down to blow a two-run lead.

Cingrani looked uncomfortable and ineffective during his outing. He gave up a leadoff single, walked a batter, gave up an RBI single to outfielder Gorkys Hernandez, then ended his evening by allowing pinch-hitter Kelby Tomlinson to hit a game-tying double. Along the way, Cingrani’s fastball velocity dropped as he dealt with what Roberts called “dead arm.”

Into the fray stepped Baez. He was walking a tightrope. And he fell. Literally.

“It seemed to be a little muddy,” Baez said through his interpreter, Jesus Quinonez. “I went to go step and I got caught with the mud.”

The defeat hurt in areas beyond the standings. Matt Kemp exited the game after scoring a run in the fourth inning because of tightness in his left quadriceps. Kemp has been a crucial cog in the offense, batting .308 with a .906 on-base plus slugging percentage. He dealt with nagging hamstring issues last season in Atlanta.

“I’ve had injuries before,” Kemp said. “You don’t want to make them worse.”

This trip will take the Dodgers to three cities and two countries. They will play four games against Arizona, the current leaders of the National League West. They will play three games against the Padres in Monterrey, Mexico. But first they must play four games in fewer than 72 hours in the Bay Area, including a doubleheader on Saturday.

In his first four starts this season, Ryu permitted one home run. He surrendered two in Friday’s second inning. San Francisco third baseman Evan Longoria powered a flat changeup over the center-field fence. Two batters later, shortstop Brandon Crawford crushed a hanging curveball for a second solo shot.

The Dodgers broke through against Giants starter Derek Holland in the fourth inning. It was their only flurry of the game. Kemp led off with a walk. Grandal smashed a double into the right-center gap. Kemp scored from first. After a walk by Cody Bellinger, Yasiel Puig tied the score on a double that could have given the Dodgers the lead, had a fan not interfered.

The umpires held up play as Bellinger rounded third. He was sent back to the bag. The Dodgers challenged the call, insisting Bellinger would have scored. A replay review upheld the initial call.

Ryu protected the lead into the sixth. He exited after getting drilled in the leg with a grounder from Giants catcher Buster Posey. Roberts trusted his relievers to protect the lead. The group failed him.

“You can talk about how hard our guys are playing, but it definitely comes down to performance and execution,” Roberts said.

“This is enough of a sample. And we’re too good of a ball club for things like that to happen.”

andy.mccullough@latimes.com

Follow Andy McCullough on Twitter @McCulloughTimes