DYNAMIC Essendon forward Irving Mosquito is almost certain to miss the entire 2021 season after scans confirmed he ruptured the ACL in his left knee against Geelong on Sunday.

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The 20-year-old hobbled from the Gabba in severe pain late in the third quarter of Sunday's heavy loss to Geelong and did not return.

Essendon general manager of football Dan Richardson said the club would support the exciting goalsneak throughout his recovery. 

"Irving made an impressive debut during our Dreamtime game against Richmond and held his spot in the senior side for the past month.

"Irving will require surgery and the club will fully support him during what will likely be a traditional 12-month rehabilitation process."

Mosquito has played four games since making his debut in the Dreamtime game against Richmond in Darwin and has been one of the Bombers' rare bright spots in recent weeks.

The injury capped off a horror day for the Bombers, blown away in the opening quarter to continue a theme of slow starts this season.

After what should have been a 90-minute bus trip from their Maroochydore hub to the Gabba took three-and-a-half hours, Essendon conceded six goals in the opening term and were never in the match.

They've won just two first quarters all season – in the opening two rounds.

Worsfold said arriving an hour before the first bounce did not contribute to the poor beginning.

"It’s just something that happened. Our preparation wasn’t ideal, that’s all I can say," he said.

"There was still stuff happening in the game that had nothing to do with sitting on the bus a little bit too long.

"We knew we were playing a really good team and they dominated around the contest.

"We didn't put anywhere near enough pressure on them, especially in that first quarter, and then they got their tails up.

"Our lack of pressure showed in that first half.

"There is a gap between where we are at and the top sides."

That gap was huge as Geelong led by 30 points at quarter-time and 59 at the half, putting themselves in great shape for a shot at Richmond in a Friday night blockbuster at Metricon Stadium.

Cats coach Chris Scott said they would likely have Zach Tuohy and ruckman Rhys Stanley available after both were late withdrawals to play the Bombers, while skipper Joel Selwood was a chance to return from his ongoing knee problem.

Gary Rohan was rested for the final quarter with a tight glute but will play against the Tigers.

Scott revealed Tuohy had been battling a knee problem.

"He was very keen to play tonight but just took a conservative approach, so I'd say 99.9 percent right (for Tigers)," Scott said.

Selwood has missed the past four matches but is closing in on a return.

"He can play this week," Scott said.

"We’ve been pretty open with training and if you watch him train you’d say he’s ready.

"I think we’ve made some errors bringing him back before we should have.

"It’s prudent to make sure he’s not only healthy but really fit and ready to play at his best. 

"If it’s not this week, it’ll be next week.

"I place a high value on cohesion at this time of year, so one of the questions is whether one game’s enough (before finals) to make sure we’ve got that.

"He slots in pretty well. Gary Ablett is pretty similar."