ESSENDON veteran James Kelly didn't exactly plan to play his 300th AFL game against Geelong, but he's delighted to reach the milestone against his old club nonetheless.

Kelly played 273 games with the Cats, including winning Grand Finals in '07, '09 and '11, and will play his 300th match at the MCG on Saturday night after being rested in round six.

"I'd be lying if I said I didn't look at the fixture at the start of the year," Kelly said with a smile on Tuesday.

"But in my overall plan I was always going to be due to miss a week.

"But it's worked out well.

"There's still a few guys who I talk to regularly there and it will be nice to be out there with them.

"Obviously if you could choose anyone to play against I would have always chosen Geelong."

Kelly reluctantly retired at the end of the 2015 season after he wasn't offered a new deal by the Cats.

But he grasped the opportunity presented by Essendon when they recruited him as one of 10 top-up players after the club was rocked by doping suspensions ahead of the 2016 season.

Kelly played 20 games and finished equal-second in the Bombers' best and fairest count.

"I didn't 'think' my career was over - it was over and I'd moved on," Kelly said, reflecting on the bizarre turn of events.

"So to get the opportunity to play again last year was something that I really enjoyed and enjoyed enough to feel like I could keep going this year.

"Looking back on the whole 18 months it's something I'm glad I took the chance at doing."

At 33, Kelly is almost certainly playing his final season in the AFL - again - but he hasn't made any firm decisions on his future.

"I learned last year to never say never," he said.

"But there's a lot of water to go under the bridge."