PHOENIX -- As the Giants head home, their worst imaginable start to the second half still isn’t over.

On Wednesday afternoon at Chase Field, San Francisco fell, 5-3, in the series finale to Arizona, which completed a three-game sweep. That took place after the Giants came out of the All-Star break and got swept in four games at Dodger Stadium. Their season-high seven-game losing streak has dropped them to 48-50, still third in the National League West but now just three games in front of the D-backs.

The Giants’ 0-7 swing through Los Angeles and Phoenix matched their longest winless road trip in the San Francisco era (since 1958). The two previous occurrences were June 20-27, 1985, and April 23-29, 1984 -- each of which featured series in San Diego and Cincinnati.

“I think we just need to come out with a little bit more fire right now,” manager Gabe Kapler said. “We’re doing everything we need to do pregame, all the preparation is sound. We need to continue that, and I think we need to just come out with a ton of fire. That’s the best thing I can share right now.”

What’s going wrong specifically? Does anything need to change?

“I think we can sum it up in [that] everything is going wrong. Everything needs to change,” first baseman Brandon Belt said. “We’ve got to hit better. We’ve got to play defense better. We’ve got to pitch better. I don’t think there’s any part of our game that is solid right now. We’ve just got to do better all around.

“I would say we need to change the attitude a little bit, but winning will do that for you. We know how to win and we can do it, but we’ve got to go out there and make it happen.”

As Belt alluded to, there are numerous reasons for San Francisco’s recent struggles -- a lack of offense and bullpen woes chief among them. Another has been some sloppy defense, which was costly again on Wednesday.

With the game tied at 2, Jake McCarthy opened the bottom of the seventh with a bunt single off Giants starter Logan Webb. Then, Sergio Alcántara knocked a single and moved up to second when center fielder Austin Slater unsuccessfully tried to nab McCarthy at third.

That led to the game-deciding moment. Jose Herrera dropped down a bunt that was fielded by Belt, who charged in from first and attempted to get McCarthy at the plate. However, Belt’s throw sailed over catcher Austin Wynns, and not only did McCarthy score, but Alcántara also came around from second to give Arizona a 4-2 lead.

The easier play was for Belt to try to get the out at first. And he acknowledged that the Giants’ skid impacted his thought process at that moment.

“It is one of those things where stuff hasn’t been going our way and we haven’t been in a lot of ballgames, haven’t been scoring a lot of runs,” Belt said. “I tried to make something happen right there, and usually when you do that, that’s a good way to screw something up. And that’s what happened -- I screwed it up. I screwed the play up. Just a bad decision.”

San Francisco’s margin for error is currently small. Each player wants to step up and make the type of game-changing play that can end the team’s funk.

“As a pitcher, I know I was out there trying to strike out everybody because I didn’t want to give up a run because I didn’t want to lose,” Webb said. “I bet you can ask any hitter in here, they want to come up and they want to hit a home run so they can score a run. All those things that we are trying to do because we haven’t won in seven days -- it’s pretty frustrating. And unfortunately, they’re not very close games, most of them. It sucks.”

Looming over the losing streak is Tuesday’s 3 p.m. PT Trade Deadline. The Giants had an opportunity this week to prove to the front office they should be buyers and add to their roster for a postseason push. Perhaps they could now decide to sell, even though that’s not what Belt wants to see.

“Obviously, I’m biased, but I know this team,” Belt said. “I know if we can get everybody on the field [healthy], we’re going to be a good ballclub. I’d love to see us make some moves to make this team better to get to the playoffs. Because that’s what I want to do -- I want to go to the playoffs. I’m not ready to give in and give up this year.”