The Giants Are Playing With Fire With Their Pitching Staff

It’s been an interesting road, but the San Francisco Giants have their five-man rotation fully set as we head into 2026. While that group was fine for the majority of 2025, it was a shell of itself by season’s end.

Whether it was due to injuries or a blockbuster trade, the roster’s starting pitch depth was virtually nonexistent to close the year.

This made Buster Posey’s offseason objective clear: upgrade the pitching staff. He was vocal about this at the organization’s end of the year press conference and repeated it several times through the early weeks of the offseason. With a starting lineup that finally has some star power in the top half, a good rotation would easily make this a playoff team.

Unfortunately, in a free-agent class headlined by aces and arms with that level of potential — Framber Valdez, Dylan Cease, Michael King, and more — the Giants opted for two affordable additions to the back end of the group.

Adrian Houser and Tyler Mahle are both coming off of their most productive seasons in recent memory, albeit in a limited amount of innings. If things go right and they’re available for the majority of the year, they both have the potential to provide great value.

However, there’s a very real possibility that both deal with injuries or simply regress to career norms and give the Giants one of the worst rotations in baseball. Yes, the group is headlined by All-Star and ace Logan Webb, but behind him, the group is full of uncertainty.

The Outlier

The one sure thing in this rotation, and potentially the most sure thing in all of baseball, is Logan Webb. The 29-year-old righty has been the definition of consistency throughout the last handful of seasons and is undoubtedly one of the best starting pitchers in baseball.

Webb has thrown north of 200 innings in each of the past three seasons and was only eight shy of that mark in 2022. In this day and age where starters are lucky to eclipse 175 innings, Webb is the epitome of a workhorse.

Not to mention, he’s been extremely effective in the surplus of availability for the Giants. Webb has been right in the middle of the Cy Young discussion in each of the last four seasons, including second, fourth, sixth, and 11th place finishes during that span.

While it’ll be difficult to win the award with names like Paul Skenes, Christopher Sanchez, and Yoshinobu Yamamoto in the National League, he definitely helped his case in 2025. With a career ground-ball rate of 57.1%, Webb has never been one to rack up strikeouts.

However, in 2025, he decided it was time for a change. Webb ended up leading the National League in the stat (224 SO) while posting a career high in strikeouts per nine innings with 9.74. If San Francisco sneaks into a wild-card spot, a lot of it will be because of this guy.

Familiar Faces

Outside of Webb, there are two returners to the Giants rotation: Robbie Ray and Landen Roupp.

Robbie Ray

It was quite the comeback season for the 33-year-old in his first full season back from Tommy John. For the majority of the season, he formed one of the best one-two punches in all of baseball with Webb.

From Opening Day until August 20, Ray had a 2.85 ERA with a 25.2% strikeout rate and 2.1 fWAR. His 154.2 innings up to that point were sixth in baseball and he was named an All-Star for the first time since 2017.

Unfortunately, he hit a wall and the last six starts of the season were rough. He posted a 8.13 ERA and walked over five hitters per nine innings. His last two starts especially stick out, giving up five earned runs against the Dodgers when the Giants were still technically in striking distance of the last wild-card spot.

While the majority of his 2025 was outstanding, regression would not be surprising considering how he finished the year.

Projections don’t love the now 34-year-old, with ZiPS predicting a 4.04 ERA in just 147 innings. However, if he can replicate his first four and a half months of last year, the Giants will be in a good spot.

Landen Roupp

It was a bit of a breakout season for Roupp and he’ll be a major factor in the Giants success this season. While his 3.80 ERA in 106.2 innings doesn’t necessarily jump off the page, it was what he did before some nagging injuries that impressed the Giants.

If you were to take out his last two starts, Roupp would’ve had a 3.11 ERA with a 3.62 FIP and 21.3% strikeout rate. At several points, he was the Giants best starter and quite the stopper when Webb was struggling in the middle of summer.

The biggest thing for Roupp is whether he can actually be on the mound. He’s never surpassed 110 innings in his professional career and was injured at several points in 2025.

Projections do like Roupp to be effective in 2026, with a 3.79 predicted ERA by ZiPS. Unfortunately, they’re also the lowest model on him in terms of availability with only 99 projected innings.

If he can repeat the production he provided in 2025 across a larger sample, Roupp can significantly raise the ceiling of this group.

The New Guys

While Giants fans probably don’t want to hear this, the two free-agent additions to the rotation are where things can go seriously wrong.

On the flip side, if these guys repeat the career years they posted in 2025, the postseason will surely be within reach for San Francisco.

Tyler Mahle

Mahle definitely has the higher ceiling of the two, but he simply hasn’t been available throughout his career.

The right-hander has only thrown a combined 125 innings since the start of 2023. Without question, Mahle’s lack of innings has significantly hindered him from becoming a reliable starter in this league.

However, the Giants are taking the risk after the 30-year-old was dominant in 2025. The 2.18 ERA and 3.37 FIP he posted were both the best marks of his career by a pretty wide margins. The caveat? It was only in 86.2 innings.

Despite being ultra-effective when he was on the mound, Mahle was close to career lows in both strikeout rate and ground-ball percentage. This led many to believe the righty got lucky throughout 2025, which explains the 4.23 xERA.

Now, if Mahle truly is healthy, then the Giants could be getting a bargain at $10 million. In the one season that Mahle made all of his starts (2021), he threw 180 innings at a 3.75 clip with over 10 strikeouts per nine innings.

Unfortunately, projections don’t see that being the case. If San Francisco gets north of 125 innings from Mahle with an ERA under 4.00, this deal should be seen as a success.

Adrian Houser

Similar to Mahle, Houser is also coming off a career year in terms of production. Despite starting the season in the minor leagues, an uptick in stuff allowed the 32-year-old to rejuvenate his career.

In 11 starts with the White Sox, Houser was amazing. He had a 6-2 record with a 2.10 ERA and 47.5% ground-ball rate. This led to the Rays trading for him prior to the trade deadline at the beginning of August.

He would struggle in 56 innings with Tampa Bay and post an ERA north of 4.50. However, it was still a step in the right direction for the right-hander. Houser posted his best marks since 2021 in innings (125.0), ERA (3.31), and FIP (3.81) through the entirety of the season.

While projections don’t love him and he could very well regress to career norms in 2026, the Giants truly believe in the uptick in stuff we saw from Houser. His most used offering — the sinker — went from averaging 92.5 mph in 2024 to averaging 94.4 mph in 2025.

More notably, some mechanical adjustments allowed Houser to add a whopping five ticks to his slider, going from 83.2 mph in 2024 to 88.1 mph in 2025.

Through his first two outings of the spring, it appears Houser has kept all of the improvements he made last season as we head into 2026. He could be a true X-factor for the Giants in the back half of their rotation.

Final Thoughts

With a lineup loaded with solidified talent with names like Rafael Devers, Willy Adames, and Matt Chapman, it’ll be up to the pitching to decide the fate of the San Francisco Giants in 2026.

With 200 innings and a sub-3.50 ERA being a lock from Logan Webb, others in the rotation will need to step up in order for this team to go anywhere. Full of uncertainty, there’s a world where the rest of this starting group is a raging disaster.

However, if things click, San Francisco is likely looking at a second-place finish in the division and a potential playoff position.

Will Robbie Ray and Landen Roupp replicate their productive 2025s? Can Adrian Houser and Tyler Mahle build off of their career years?

A lot is riding on the four names behind Webb, and them stepping up will be huge for the Giants’ outlook in 2026.

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