In 2019, the D-backs crushed left-handed starting pitching.

This season, it’s been a different story, and Thursday night’s 5-1 loss to the A’s at the Coliseum was another example of what a difference a year has made. One night after struggling against Oakland lefty Jesús Luzardo, Arizona mustered only one run -- a fifth-inning homer by Eduardo Escobar -- against another southpaw, Sean Manaea.

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“It's not like we can't handle lefties,” D-backs first baseman Christian Walker said. “It's just kind of the way it's been going for us. Maybe, if anything, we’re seeing lefties really well and we're trying to do a little too much and trying to force it and not let the game come to us. I don't like feeling complacent or content with anything like that, but at the same time, you've got to be fair to the hitters and just chalk it up to baseball being difficult sometimes.”

Last year, the D-backs led the Majors in OPS against lefty starters with an .815 mark, and they were also first in batting average against them, hitting .275.

This year, Arizona is 0-6 in games started by left-handers, and coming into Thursday’s game, it ranked 29th in OPS (.538) and 24th in batting average (.207) against them.

“I feel like the change of speeds front to back [of the zone], maybe,” D-backs manager Torey Lovullo said. “The back-foot slider might be giving some problems. We're definitely getting pitched to, we're getting game-planned against. But we've got some really good, capable right-handed hitters that'll make the adjustment.

"I believe in their ability to help us score some runs. I thought when we were in Summer Camp that left-handed pitching was going to be something that we were going to feast on. It hasn't been the case. We're going to make some adjustments.”

Luzardo and Manaea are both quality pitchers, as are the other lefty starters the D-backs have faced. They've gone up against Clayton Kershaw and Julio Urías of the Dodgers, Joey Lucchesi of the Padres and Kyle Freeland of the Rockies.

Lovullo, though, doesn’t want to give those pitchers too much credit.

“We're very respectful of our opponent at all times,” Lovullo said. “But I want to put it on us, because I believe in our guys, so we'll make some adjustments. I believe enough in what they've given me in the past to make me believe that they'll be OK.”

On Thursday afternoon, D-backs general manager Mike Hazen mentioned that one of the things he would be looking at possibly adding before the Aug. 31 Trade Deadline is more offense. When pressed if a right-handed hitter would make more sense than a lefty given the way they’ve played this year against southpaws, Hazen didn’t want to go that far.

Six games is a small sample size. In addition, while two of the team’s better hitters -- outfielders David Peralta and Kole Calhoun -- are lefties, Hazen cited the presence of switch-hitters like Escobar and Ketel Marte in terms of helping balance the lineup.

What Hazen really would like to see is more power. The D-backs are tied for 25th in the Majors with 22 home runs. They've played 26 games while the four teams behind them have all played fewer -- the Rangers (21 homers in 24 games), Pirates (19 in 21), Marlins (17 in 18) and Cardinals (13 in 14).

Instead, Arizona has relied more on singles and doubles, something that is tough to continue over time.

“I think we have put some games together that are not likely sustainable from a hits-per-night basis,” Hazen said. “We know how the game runs now. Getting four singles to score a run is not a sustainable way of driving offense. Getting on base, hitting for power, driving the baseball -- something we have done with our lineup in the past and are capable of doing and have shown spurts of this year. ... I think if you talk about wanting to be a playoff team, I don’t think it’s unreasonable to want to expect that on a more consistent basis.”