White Sox's trade for Luis Castillo might not have fixed their biggest issue

The Chicago White Sox are having an incredible resurgent 2026 season. They entered the year as a bottom-of-the-barrel team, and now as August winds down, they're sitting atop the American League Central.

But their lead is just 2.5 games over the Cleveland Guardians, and things could easily unravel from here if they have a bad stretch of games. Unfortunately for the White Sox, they also have a glaring issue that could really hurt them down the stretch.

As Kerry Miller of Bleacher Report highlighted, the White Sox still have a huge "red flag" in their starting rotation, as the Luis Castillo trade hasn't resolved the biggest issue the White Sox had entering the deadline.

White Sox's Luis Castillo trade hasn't fixed 'red flag' issue

"Chicago White Sox: Not Enough Starting Pitching," Miller writes. "The White Sox keep holding steady atop this division and are extremely likely to make the postseason. But this simply is not an October-caliber starting rotation."

Sean Burke has a 3.27 ERA on the season, but how he fares in a postseason environment is unknown. But even if the White Sox can rely on him, their other options are far from ideal.

Castillo, meant to be a big trade pickup, has a 5.89 ERA in four starts for the White Sox since the trade. He's posted -0.2 bWAR on the season with Chicago, already proving to be a net negative for his new team.

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Davis Martin is hurt and has a 4.32 ERA on the season. Anthony Kay has a 4.09 ERA, and while he could be decent in October, there's not a lot of trust in the left-hander.

Jose Urquidy has a 5.68 ERA for the White Sox, and he's currently their No. 4 starter as the season winds down in August and September.

Erick Fedde can't be trusted in the postseason either, even with a mediocre 4.18 ERA instead of his 5.49 ERA from a year ago.

The White Sox have a big question in their starting rotation, and unless someone can close out the year strong and enter the postseason hot, it might prove difficult to win a series with their starting pitching.

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