Star Bomber Mark Mercuri will be missing for the next three rounds after it was confirmed this afternoon that he will have to undergo arthroscopic surgery. An MRI scan this afternoon revealed Mercuri had damaged surface cartilage in his right knee. Mercuri did the damage early in the second quarter of last Saturday's match against Richmond when he landed awkwardly after a marking contest. There was more positive news on the Steven Alessio front with the big ruckman expected to be available for this Sunday's Grand Final replay against Melbourne.

""We thought Mark we need to have an arthroscope and the scan confirmed that. However the damage isn't as significant as we first thought so we are hopeful he won't be out of action for more than three weeks,"" Essendon football manager Matthew Drain said tonight.

Drain said the news looked more promising for ruckman Steven Alessio. ""He strained his knee but it has improved since Saturday and we are hopeful he will play this weekend,"" Drain said.

On another positive note, mid-fielder Chris Heffernan is nearing a return to football after a knee injury. Heffernan hasn't played a senior game since injuring his knee in the pre-season but he faces a fitness test this week to okay his return. Heffernan is likely to return through the VFL side and may be eased back into the action against Sandringham this Saturday or the following weekend against Box Hill.

Joe Misiti is still four weeks away from returning while Michael Long will be 2-3 weeks away from the action. Long had an arthroscope last week but his rehabilitiation was hampered by tonsilitis. Dean wallis faces a fitness test after injuring his hamstirng.