Diamondbacks Face Intimidating Pitching Matchups vs Giants

The Arizona Diamondbacks have fallen below .500 after being swept in disheartening fashion by the Miami Marlins. Beginning Monday, the D-backs will welcome their division rival San Francisco Giants to Chase Field for a four-game series.

The 'easy' portion of Arizona's schedule is now over. Though the Giants have hit a rough patch of late, they are full of talent, and are 3.5 games ahead of Arizona at 45-39.

The Diamondbacks are in dire need of some winning baseball, but that may be tough to accomplish against a sturdy San Francisco pitching staff.

Below are the matchups for each game:

Arizona Diamondbacks vs San Francisco Giants Pitching Matchups

Monday, June 30: RHP Ryne Nelson (3.71 ERA) vs RHP Logan Webb (2.52 ERA)

Right-hander Ryne Nelson has been one of the more valuable arms on Arizona's staff, both as a reliever and a starter. Though he has been held short by pitch count limitations, Nelson has turned in excellent lines in his three prior starts.

Nelson has allowed exactly one run in each of those outings. Over his past 15.2 innings, he's allowed three runs (two earned) and has struck out 14.

Nelson is 2-0 with a career 3.11 ERA against San Francisco. He struck out nine and allowed one run over 6.2 innings the last time he started a contest against the Giants.

Logan Webb is the ace of the Giants' staff. He's excelled to a 2.52 ERA in 17 starts, and has a FIP of 2.25 to back it up.

Webb has generally been known as a ground-ball pitcher. While that is not untrue, as he's posted a 54.5% ground ball rate (91st percentile in MLB per Statcast), he's also striking out batters at the highest clip of his career, with a K/9 just north of 10.00. His strikeout rate is a career-high 27.7%.

He's thrown six straight Quality Starts, and has gone seven or more innings eight times. He's finished the eighth inning twice. Webb will be a brutal challenge for Arizona's hitters.

Tuesday, July 1: RHP Zac Gallen (5.75 ERA) vs RHP Hayden Birdsong (4.13 ERA)

2025 has been anything but kind to Zac Gallen. Though there have been some dominant starts, the recent stretch has been riddled with poor performance. His 5.75 ERA is the worst among qualified starters.

Gallen simply isn't missing bats and is struggling to avoid leaving his pitches in hittable spots. He's also walking nearly four batters per nine — the highest clip of his career.

Gallen has been solid enough against the Giants, pitching to a 6-5 record and a 3.94 ERA in his career. Most recently, he delivered six innings of one-run baseball with 11 strikeouts against San Francisco in September 2024, but that version of Gallen appears to be long departed.

23-year-old righty Hayden Birdsong had an excellent beginning to his 2025 as a reliever, but has struggled to 6.38 monthly ERA in June as a starter. He's given up 12 runs (11 earned) in his last 8.1 innings.

The D-backs lit him up for three runs on a pair of homers back in May, but that was in long relief. Since re-entering the rotation, Birdsong has surrendered 22 runs (20 earned) in 33.1 innings. He has a 5.40 ERA in his seven starts this year.

Wednesday, July 2: RHP Merrill Kelly (3.49 ERA) vs RHP Landen Roupp (3.43 ERA)

Merrill Kelly has maintained his reputation as a steadying presence out of the D-backs' rotation. His 3.49 ERA is underscored by a 3.32 fielding independent pitching.

Kelly has been hitting his spots, providing length and even returning to near-2023 levels of strikeouts (9.18 K/9). Kelly has struck out seven or more batters in his last five starts, and he's only walked six in that span.

With that said, Kelly has not had a scoreless outing since June 4, and has given up three or more in each of his last three starts. He allowed five runs in five innings his last time out, although two were unearned.

Landen Roupp is another young right-hander in this Giants rotation. He's had some polarizing results, but has an overall impressive 3.43 ERA. His peripherals are not far off that number, either.

He's posted a six-plus inning Quality Start three times in June, but was also lit up for six runs in just 1.2 innings on June 14. Roupp has not faced Arizona as a starter yet, but threw four scoreless innings of long relief against the D-backs in September of 2024.

Thursday, July 3: RHP Brandon Pfaadt (5.38 ERA) vs LHP Robbie Ray (2.75 ERA)

Brandon Pfaadt battled through some adversity for five solid innings against the Miami Marlins his last time out as he looks to regain his footing after a streak of poor performances.

Pfaadt has been bit by hard contact for much of the season, and while he has turned in a few more-pleasing box scores in recent starts, he has not looked to have the same level of command and has struggled to miss bats frequently.

Saturday's start showed some progress, as he punched out seven, but he still has yet to go further than five innings since May 25.

Pfaadt was knocked around by the Giants in May, giving up four runs on six hits (including a grand slam) and three walks over just four innings.

Meanwhile, Diamondbacks' old friend Robbie Ray has had a resurgent 2025. His 2.75 ERA is backed by his peripherals, he boasts an 8-3 record, and he's striking out over 10 batters per nine.

Ray has delivered three Quality Starts in the month of June. He punched out nine Arizona hitters over six innings back on May 13, only allowing three earned runs despite giving up seven base hits and three walks.

The 33-year-old is stranding 80.8% of baserunners in 2025, and has been pitching like an ace. He has not given up more than four runs in a start this season.

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