ESSENDON'S slide out of the top eight has James Hird searching for answers, but the Bombers coach says he won't "overreact" to the form slump.

The Bombers have lost their past five games and six of their last seven since beating the Western Bulldogs in round 14. Four of those defeats have been by margins of more than 10 goals.

Hird said the Bombers were working to discover the reasons behind the drop and how to fix things for next season, but that the first half of the season - which saw Essendon win eight of its first nine games - highlighted not all was wrong.

"We're going to sit down and go through it, and we have been going through what we need to improve on," Hird said on Thursday.

"But we've done a fair bit right in the first half of the year, too, so you're very careful to overreact and throw everything out.

"There's some things we need to adjust and we will adjust, but we're not going to throw everything out either, because we've got guys who have taken their football a long way in the first three quarters of the year. But at the moment we're struggling a bit."

Ahead of the Bombers' meeting with Richmond on Friday night, Hird denied the club had gone backwards in 2012 after making the finals last year.

He cited the team's win/loss record - if the Bombers beat the Tigers they will have won more games than in any year since 2004 - and their close defeats to top-three sides Collingwood, Adelaide and the Sydney Swans.

"We'll look at it at the end of the year," Hird said.

"There's still two games to go and we'll look at whether we've come forward or gone back, but what we do need to look at is…have we laid a foundation to then go forward again next year, and then go forward the year after?

"And that's where I'm very confident we have."

With defenders Dustin Fletcher (hip) and Jake Carlisle (ankle) set to miss the Tigers clash, Tayte Pears is likely to return, while first-year forward Nick O'Brien will make his debut.

O'Brien, a running half-forward who impressed last week in the VFL, was a third round selection at last year's NAB AFL Draft.

"He would have played a lot earlier this year but hurt his foot in round two or three with Bendigo, which put him back a bit," Hird said.

"[He's] a running machine and another young kid to come into our team who I think will [have] a big future for our footy club."

Callum Twomey is a reporter for the AFL website. Follow him on Twitter at @AFL_CalTwomey.