SAN FRANCISCO -- A smattering of boos sprung from the stands at Oracle Park on Sunday afternoon after a particularly rough second-inning sequence in which Ketel Marte singled and ended up at third base following a pair of bad throws from the Giants’ defense, allowing the D-backs to score their fifth run of the day against rookie Shaun Anderson.

The play encapsulated the blunders that undermined the Giants during their grim 1-6 homestand, which concluded with a 6-2 loss to the D-backs. They were outscored 34-8 over this three-game series and were swept at home for the second time this season.

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“I can’t remember when we had three consecutive games with that kind of baseball we just played,” manager Bruce Bochy said. “Across the board -- baserunning, defense, pitching -- this was, no question, the worst series I’ve seen in a while.”

After losing five in a row, the Giants are a season-worst 10 games below .500 with a 21-31 record.

Here are three questions facing the club following Sunday’s finale.

1. How will the Giants solve their rotation issues?

Anderson struggled in his third start for the Giants, yielding six runs (four earned) on nine hits over five innings. Bochy said he thought Anderson left too many balls up early before making an adjustment later in his outing.

“They’re a really aggressive team,” Anderson said. “I made some bad pitches early, and they got to them.”

San Francisco’s starters were hit hard this series, with Drew Pomeranz, Andrew Suarez and Anderson combining to give up 20 runs over 11 2/3 innings. The Giants’ rotation has a 7.15 ERA in 22 games this month, the second-highest mark in the Majors behind only the Rockies.

Length has been an issue, too. The last time the Giants got at least seven innings from a starter was Madison Bumgarner on April 13. The Giants’ streak of 36 consecutive games without at least a seven-inning outing from their starters is the team’s longest streak in the last 100 years, according to Stats LLC.

“We’ve got to pitch better,” Bochy said. “That’s the obvious. We’ve got to get a little deeper into games. It’s about execution. We’ve got to hit our spots, get the ball down, go in and out. All three guys were off, and we paid for it.”

Their starters’ struggles have put a strain on the bullpen and forced the Giants to call up a pair of fresh arms in Dereck Rodriguez and Sam Coonrod, who tossed a perfect eighth in his Major League debut on Sunday.

The Giants currently have a vacancy in their rotation after optioning Suarez to Triple-A Sacramento on Sunday to clear a roster spot for Coonrod, though they have not yet decided who will take his turn. Rodriguez and Tyler Beede are both candidates for that spot. Either way, it’s clear the Giants’ rotation is in need of help.

2. Is Mike Yastrzemski the answer in left field?

After going hitless in three-bats Saturday in his Major League debut, Yastrzemski delivered a three-hit performance against the D-backs on Sunday. His first hit didn’t play out perfectly -- after blooping a single to left field in the second inning, Yastrzemski rounded too far off the base and was promptly thrown out. Still, the 28-year-old outfielder helped atone for the blunder by singling in the fifth and delivering a leadoff double in the seventh to finish 3-for-4.

“That’s not really how you draw it up in your mind before it happens,” Yastrzemski said. “But you’ll take them any way they come. You never complain about a hit.”

The Giants have been starved for production in left field, where nine different players have combined to post an MLB-worst .425 OPS this season. Yastrzemski, a left-handed hitter, is expected to platoon with Tyler Austin in left for now, though he will likely start the next three games in Miami because the Giants are due to face a trio of right-handers.

It’s too early to say whether Yastrzemski will sustain those results in the Majors, but Sunday marked a promising start.

“It was good to see him have success here in his second game,” Bochy said. “I thought he threw out some good at-bats. I’m happy for him because he’s worked for a while to get there. I think he signed in 2014, and made his debut now. That’s good for him. Hopefully, he’ll keep that going and help us, because we need production there.”

3. Can they take advantage of a soft spot in their schedule?

The Giants will embark to Miami, Baltimore and New York (to play the Mets) for an 11-day, nine-game swing through the East Coast. The Marlins (16-34) and Orioles (16-37) are among the five MLB teams with worse records than the Giants, creating an opportunity for San Francisco to try to climb out of its rut.

“We’ve got to huddle up here,” Bochy said. “The day off [Monday] will give them a chance to wash this one off. This road trip I’m hoping brings them together and gets us back to playing the kind of ball we need to play.”