Eichel participated in warmups but was replaced by Tage Thompson in the lineup.
The 24-year-old only has two goals and 14 points in 16 games after scoring a career-high 36 goals last season.
In an interview with WGR 550 in Buffalo Thursday, head coach Ralph Krueger revealed that Eichel has been dealing with an injury since training camp, which impacted his preparation for the season.
"Everybody has to realize that he had an injury pre-training camp that pretty well parked him from doing a lot of physical activities for multiple weeks," Krueger said, according to NHL.com. "He started training camp a week delayed. The game pace that we've had and the forced almost eight-day break (for NHL COVID-19 protocol) that everyone had a few weeks ago, he has worked as hard as anybody else to get himself up to speed. But all the circumstances are preventing him from being at 100 per cent physical condition and shape because we just have no practices and we have no training time between the games."