Zevachim 104A

ומאי אחר הפשט ⁠– קודם שנראו להפשט, אחר שנראו להפשט.

and what does it mean by the phrase: After flaying? It means before the moment the offerings became fit for flaying, and after the moment they became fit for flaying, i.e., before and after the sprinkling of the blood.

מאי רבי ומאי רבי אלעזר ברבי שמעון? דתניא, רבי אומר: הדם מרצה על העור בפני עצמו. וכשהוא עם הבשר, נולד בו פסול בין קודם זריקה בין לאחר זריקה ⁠– הרי הוא כיוצא בו.

The Talmud clarifies: What is the opinion of R' Yehuda HaNasi, and what is the opinion of R' Elazar, son of R' Shimon? Their opinions are as it is taught in a baraita: R' Yehuda HaNasi says: The blood effects acceptance of the hide by itself, after it has been flayed, even if the flesh is disqualified. And if, when the hide is still with the flesh, a disqualification appears on the flesh, whether before the sprinkling of the blood or after the sprinkling of the blood, then the halakha with regard to the hide is parallel to the halakha with regard to the flesh: Both are burned.

רבי אלעזר ברבי שמעון אומר: אין הדם מרצה על העור בפני עצמו. וכשהוא עם הבשר ⁠– נולד בו פסול קודם זריקה, הרי הוא כיוצא בו. אחר זריקה, הורצה בשר שעה אחת; יפשיטנו, ועורו לכהנים.

R' Elazar, son of R' Shimon, says: The blood does not effect acceptance of the hide by itself. And if, when the hide is still with the flesh, a disqualification appears on the flesh before the sprinkling of the blood, then the halakha with regard to the hide is parallel to the halakha with regard to the flesh: Both are burned. If a disqualification develops on the flesh after the sprinkling of the blood, the flesh was already accepted for a time. Therefore, even though the flesh is disqualified, the priest may flay the animal before it is burned, and its hide goes to the priests.