ESSENDON'S Mark McVeigh has always felt a sense of guilt about his sickening, accidental collision with James Hird in Perth in 2002, which smashed the champion's cheekbone, eye socket and sinus cavities.

Now, more than six years later, karma of a more tangible kind has come to visit the Bomber midfielder, the injury for which he had surgery at Richmond's Epworth Hospital yesterday the final result of that infamous impact between knee and head all those years ago.

"They reckon this stems back from my collision with James Hird, which is quite amazing," McVeigh said as he headed into hospital for the operation to repair damaged knee cartilage.

"I've battled with it ever since and I've never really had anything done. But it flared up unfortunately, and cartilage has come off my femur and a bit of it's floating under my kneecap, which is causing a bit of pain."

McVeigh had the chance to tell Hird personally of the belated twist to a shocking injury tale when Hird rang to wish him all the best for his appointment with the surgeon's knife.

Karma? "He reckons it is," McVeigh smiled. "He said: 'See, all those years ago what you did to me?' That's just the way it is. It wasn't just that, I've been hit there over the years afterwards as well, but that's when it all started."

McVeigh, in the middle of an outstanding season and a contender for Essendon's best and fairest, conceded initial shock, then anger, earlier this week when told he would require surgery.

"I was filthy, I must admit, because I went into the MRI scan thinking it was just one those where they say: 'Look after it, and get it done at the end of the year', but unfortunately I can't continue.

"The surgeons say a month to six weeks. If I respond well, I'd like to say three, you never know. I've always responded well to surgery. Everyone says structurally, my knee's great.

"It makes it tougher, because the side's starting to turn things around, and I want to be part of that when we've been through such lows this year. I just want to be part of it and help the young guys develop, so that's more disappointing for me. I've performed probably the best I have in my career, but I feel I've (still) got a lot to go, and if I don't play this year, I know I can put a lot of effort into my pre-season next year."

McVeigh also acknowledged the unfortunate timing of the surgery, given the two-match internal suspension handed to another key midfielder in Andrew Lovett for missing a training session, but reaffirmed support for the decision, of which he, as a member of the leadership group, was part.

"We've got a strict code at Essendon that we've stuck to, and unfortunately 'Lovey' missed training again, so the players felt it was in the best interests of the club that he miss a couple of games, but in saying that, we need him to get back in the side because he's so much value to us."

McVeigh said he didn't believe Lovett's place on the Essendon list should be endangered by his latest off-field misdemeanour.

■The AFL will use four boundary umpires for all matches in this year's finals series. AFL umpiring manager Jeff Gieschen said having an extra umpire on each side of the ground would enable them to be in the best position to judge line decisions.

He said the system had been successfully trialled in past pre-season games and during this year's Hall of Fame tribute match.