Looking back at the 2023 regular season, we know that the Astros’ under-performed their win percent by about three wins. The Astros faced substantial headwinds during the 2023 season—most notably injuries on both offense and defense. But, even with those injuries, the Astros’ W/L record was below what is expected for the runs they scored (RS) and the runs their pitching staff allowed (RA).
Why do I said that? The Pythagorean W-L record (or “Pythag” for short) is used to estimate the Win Percent that results from a given RS and RA. According to the traditional Pythag at Baseball-Reference, the Astros’ 90 win season in 2023 fell three wins short of the Pythagorean Record of 93 wins.