SAN DIEGO -- The D-backs' offense, which had been prolific through the first six games of the year, struggled Wednesday as a quartet of Padres pitchers shut them down, 4-1, at Petco Park.

Arizona had scored at least five runs in each of its first six games, but San Diego starter Joey Lucchesi (2-0) kept the D-backs off balance through the first five innings.

Robbie Ray (0-2) matched Lucchesi through the first four innings before giving up single runs in the fifth and sixth innings.

Here are three takeaways from the D-backs' road trip:

1. The offense might be better than we thought

When they traded Paul Goldschmidt and lost A.J. Pollock to free agency, it looked like the D-backs might have trouble scoring runs this year.

Add to that a poor spring at the plate for the team and the expectations were not high.

Instead, the bats started hot. Arizona smacked 14 homers in the first six games of the season and has now collected 17 doubles.

"This is a really good team," Ray said. "I think we can hit. We've got some really good power hitters on our team."

That would appear to include pitcher Zack Greinke, who hit a pair of home runs in Tuesday night's win.

"We're hitting the baseball extremely well," D-backs manager Torey Lovullo said. "I've been very satisfied with that. We had an emphasis on hitting with runners in scoring position throughout Spring Training and the offseason and these hitters have done a fantastic job. I'm very pleased."

2. The starters have to pick it up

While Arizona's offense was looked at as a possible weakness, the starting rotation was supposed to be a strength.

However, the starters had an ugly opening series in Los Angeles.

Greinke, Robbie Ray, Zack Godley and Luke Weaver combined to pitch 18 1/3 innings and allow 21 earned runs (10.31 ERA) in the four games, and only Godley pitched into the sixth inning.

That put a strain on the D-backs' bullpen and forced them to add a 13th pitcher -- right-hander Jon Duplantier -- to try to alleviate the stress.

"I know they're going to be fine," Lovullo said of his starters after the Dodgers series. "I want to see them get after it a little bit and I know that will be the challenge to them."

That was the case against the Padres as fifth starter Merrill Kelly had a nice debut and Greinke and Ray pitched better in their second starts.

"I feel like the rotation is coming around a little bit," Ray said. "Guys the second time around are feeling a little better."

3. Lovullo is staying true to his word

This spring, Lovullo said that in evaluating himself from last year, he realized he wanted to be more flexible when it came to his lineups. In the past, Lovullo would make his lineups out days in advance and stick to them regardless of whether a player was swinging a hot bat.

Lovullo showed that he meant what he said after he found a way to get Christian Walker into the lineup after the slugging first baseman hit a homer on Opening Day and a pinch-hit homer the day after that.

Lovullo was not afraid to sit Jake Lamb for the first two games of the Padres series, and he also had Lamb shift back to third base as a way to keep both his and Walker's bats in the lineup. (Though Lamb suffered a left quad strain in Wednesday's game, according to Lovullo, and likely will have an MRI on Thursday.)

"It's no mystery that Christian Walker is smashing the ball and we want him in there as often as we can possibly have him in there," Lovullo said. "I think certain things develop before us and then we make decisions based on what we see."