But Schefter and Yates reported doctors believe Baldwin will be healthy for Seattle's Week 1 matchup with the Denver Broncos on Sept. 9.
Seahawks head coach Pete Carroll acknowledged Tuesday that Baldwin had a "sore knee" when he arrived for the team's training camp.
"We’re going to give him a couple of weeks here before we bring him back out to make sure we’ve ramped him back up properly," Carroll said, per John Boyle of the Seahawks' official site. "He came into camp a little bit off, so we just want to make sure that we take care of him."
Baldwin was once again Seattle's leading receiver in 2017. He caught 75 passes for 991 yards and eight touchdowns en route to a second straight Pro Bowl.
The Seahawks signed Brandon Marshall and Jaron Brown in the offseason, but Baldwin remains the team's most important receiver.
It would be less than ideal were he to miss the entire preseason, but getting him healthy for the regular season is Seattle's top priority. The Seahawks will be in trouble if Baldwin's injury continues to linger into September.