The Philadelphia Phillies are determined to defend their division title and finally capture that elusive World Series crown. The early part of the season has shown encouraging signs, but it’s also revealed a few flaws that the team must address sooner rather than later.

It’s far too early to panic or assume they won’t fix their issues, but early signs of regression are never ideal for a season built on high expectations. One of the most promising developments has been the rise of left-hander Cristopher Sánchez, who’s looked like a budding star after his breakout 2024 All-Star campaign. However, his ascent seems to be coinciding with a troubling decline from the team’s longest-tenured pitcher, Aaron Nola.

Sánchez’s emergence has essentially filled the void left by Nola’s struggles

After a strong 2024 that earned him an All-Star selection—finishing with an 11-9 record, a 3.32 ERA, and 153 strikeouts over 181 2/3 innings—Sánchez was rewarded with a four-year extension. Coming into 2025, he’s taken another leap forward, with increased velocity and refined mechanics that have Phillies fans excited.

He lived up to the hype with a career-best performance on Thursday, striking out 12 over seven innings to secure his second win of the season. So far, he’s 2-0 with a 2.96 ERA and 31 strikeouts in 24 1/3 innings. His 11.5 strikeouts per nine innings, per FanGraphs, would be a career high and a significant jump from last year’s 7.58. But as Sánchez shines, Nola’s struggles have cast a shadow.

Nola’s 2025 season has started off rough. In his latest outing on Wednesday, he gave up nine hits, four walks, and 11 earned runs—including two homers—in just 5 1/3 innings, dropping him to 0-4 with a 6.65 ERA through four starts. His 9.2 percent barrel rate is the highest of his career, according to MLB.com’s Todd Zolecki.

What’s concerning is the ongoing unpredictability surrounding Nola, even after 11 seasons in Philadelphia. He’s alternated between mid-3.00 and mid-4.00 ERAs over the last several years, and now his fastball velocity appears to be dipping as well. If things continue on their current trajectory, this season may fit right into that up-and-down pattern.

There is a silver lining: Nola’s 4.02 expected ERA suggests he might be suffering from some poor luck. The Phillies’ rotation, led by two-time Cy Young runner-up Zack Wheeler and bolstered by the addition of Jesús Luzardo, has the potential to be historically dominant. If Nola can rediscover his form, this group could be remembered as one of the best rotations in franchise—and maybe even league—history.