This was going to be the night the D-backs snapped a pair of losing streaks. A four-run first inning, followed by a three-run second? Yeah, it was going to happen.

Even when the Giants scored three runs in the second, the D-backs were still in good shape.

Then, in the eighth, right-hander Humberto Castellanos was one strike away from getting out of a bases-loaded jam before Mike Yastrzemski smashed a go-ahead grand slam to lead the Giants past the D-backs, 9-8, on Tuesday night at Oracle Park.

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It was Arizona's 12th consecutive loss and its 21st straight defeat on the road. The D-backs have lost 26 of their past 28 games and 35 of their past 40.

No team has lost as many as 20 straight road games since the 1963 New York Mets, who matched the 1943 Philadelphia A's for the Major League record of 22, a mark the D-backs could tie Wednesday night.

There have been some tough losses during the streak, but this one seemed different. You could see it on the faces of players like Christian Walker, David Peralta and Eduardo Escobar, who stayed in the dugout after the final out, their faces registering the disbelief.

"That hurts," said second baseman Josh Rojas, who went 3-for-5. "It hurts a lot. I mean, any time you lose it hurts, but for it to be in that kind of fashion -- a four-run homer, a grand slam, in the bottom of the eighth. That one was tough."

Castellanos had Yastrzemski down 1-2 before the Giants outfielder deposited a changeup into McCovey Cove.

Things seemed to be going the D-backs' way from the start. They chased Giants right-hander Zack Littell, who was serving as an opener, after the first six batters of the game reached and Arizona had a 4-0 lead.

The D-backs then went to work against left-hander Sammy Long, who relieved Littell and gave up four runs over five innings.

With an 8-5 lead heading into the bottom of the eighth, the D-backs still felt good about their position.

And then it unraveled.

First, left-hander Joe Mantiply put two runners on before giving way to Castellanos with two outs. Castellanos walked pinch-hitter Curt Casali, before then giving up the grand slam to Yastrzemski.

"You know, it'd be a different story if we didn't play a good game," Rojas said. "And if we came out of the blocks slow and they just beat us down. But to have a game where you're leading, what, seven, 7 2/3, you've got the lead, and then they hit a four-run homer. It wasn't just a homer. It was three inches from being foul ... down the line, hugs the pole, just barely stayed fair, on a good pitch, good hitter. That one stung. That one stung a lot."

Now, the D-backs have to try to find a way to put yet another defeat behind them and get back after it for the final two games in San Francisco. The baseball calendar doesn't slow down or pause just because you've suffered a tough loss.

Making sure the team can bounce back falls to manager Torey Lovullo.

"I'll never throw my hands up, and I'll never give in to what's happening around me," Lovullo said. "On a daily basis, it's my responsibility to make sure that the team is getting taught at the highest level by our coaches. We're just going to continue to turn the page every day and create some new opportunities the following day.

"I think we've got to understand that we build and create our own environment and create our own situation. And we've got to go out there, pridefully, and expect to win games. I don't want there to be a negative thought, and I don't want things to creep into the guys' heads about feeling sorry for themselves. This is a big-boy league. This is a man's game. So we've got to fight, and we've got to earn it. And that will never stop."

The fight continues Wednesday night.