Thielen was absent from Thursday's practice due to an illness, Mark Craig of the Minneapolis Star Tribune reports.
Thielen wasn't listed on the Vikings' first Week 6 injury report, but according to Craig's source, the wide receiver began to feel sick Wednesday and is "legitimately" under the weather. Consequently, Thielen's status will be one to monitor as the weekend draws closer. If he's not 100 percent or held out Sunday against the Eagles, Bisi Johnson and Laquon Treadwell would experience an uptick in snaps alongside starter Stefon Diggs.