A week after he starred against Sydney, Essendon captain Dyson Heppell struggled to have an impact in their tight AFL loss to Hawthorn.
Bombers coach John Worsfold says the midfielder is carrying an injury and didn't train before Saturday's clash.
He says Heppell has been managing the injury for several weeks.
Asked what's wrong with Heppell, Worsfold replied: "It's complicated."
Heppell had 25 disposals and struggled noticeably in the first half against Brownlow Medal favourite Tom Mitchell.
Essendon quelled Mitchell's influence in the second half when their midfielders shared the load against him.
Worsfold said Heppell "worked his backside off" on Saturday but said the skipper was down compared with his game against the Swans.
"There's no doubt he wasn't moving as freely as he has over the last few weeks," the Bombers coach said.
"I'd expect he'll get up for next week but that's not a given."
The loss means Essendon will need a miracle to make the finals, given their last three games include Richmond and an away game against Port Adelaide.
After winning six of their past seven games, Worsfold felt Essendon were off the boil against Hawthorn.
"I really felt as though we didn't play at our best today. We made too many errors at times when we weren't under enough pressure to make those errors," he said.
Jake Stringer limped off in the third term with an ankle injury but he played out the match.