The 2009 Michelsen Medal winner ruptured his ACL in a practice match against Rochester.

Originally, the Dragons didn't think the injury was season-ending, but scans on Friday revealed the popular Dragon requires a knee reconstruction.

"The structural tests that we did on the day seemed to indicate it wasn't an ACL injury, but the scans said otherwise,'' Sandhurst coach Ashley Connick said.

"It's a season-ending job and we're all really disappointed for Lee.

"He's in as good a spirits as he can be. He was at our practice match (on Saturday against Echuca) to support the boys.

"For the past couple of months we had been looking for a midfield coach, but Lee will fill that role for this season now.

"He'll do his rehab and still be heavily involved with the club."

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Connick said Coghlan had been one of the players that had impressed him most in his first pre-season with the Dragons.

"Lee had a great pre-season, he was probably in the top two or three players at the club,'' Connick said.

"He looked like he was in for a really good season."

While Coghlan's ball-winning ability, creativity and leadership will be missed by the Dragons, Connick said the club's midfield depth was its greatest strength.

"We bat pretty deep through the midfield,'' Connick said.

"We'll have seven or eight guys run through there and it opens the door for more time in the middle for other players.

"Joel Wharton has been really good. Zac Pallpratt (who was coming off a knee injury last year) has done 80 per cent of our pre-season compared to zero last year and he's probably been our best player across our two practice matches.

"Nick Stagg will step into that role as well to help fill the void. There's still Adam Parry, Blair Holmes and Andy Collins plus Jake McLean has run through the midfield in the pre-season as well."

The Dragons have had two solid hit-outs against Rochester and Echuca and they complete their pre-season campaign this Saturday against Geelong league power St Mary's.

"We think we snuck over the line by a goal against Echuca,'' Connick said.

"The talk in the Goulburn Valley is that Echuca will be in the top three, but in saying that the game can be misleading because both teams had a few out.

"On paper we probably didn't have the same amount of talent on the park as we did the previous week, but overall I thought we played much better."

Sandhurst opens the BFNL season under lights at Kangaroo Flat on April 13.

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