The Cowboys placed Brown (knee) on the PUP list Friday, Jon Machota of The Athletic of reports.
Brown had a knee scope that caused him to miss June minicamp. The 23-year-old was expected to be ready for training camp, but it appears he will spend at least the start of camp on the PUP list. Brown can be activated at any time between now and the end of preseason, but he'll be unable to practice until the team elects to do so.