Lining up for the Magpies VFL side, Keeffe collected four kicks, two handballs and two marks in the team's win over Essendon at Victoria Park on Saturday.
His numbers weren't groundbreaking, but the 23-year-old was just pleased to be back playing football.
"It was good to get out there, and good to get among the boys, and good to be among a win I guess," Keeffe told AFL.com.au.
"Obviously it's a relief. I didn't have too many confidence issues coming in. I've done the work, I've spent the time off and the knee's felt good for a about a month or so with training as well so that wasn't my issue coming in. I was more scared about 'will I get a kick?'"
Keeffe was one of four big-name Magpies to suffer serious knee injuries in 2012, and it was that company in the rehabilitation program that helped him through the tough times.
"I think I just learned off Luke Ball, Brent Maccaffer and Andrew Krakouer. They just said 'you've got to have confidence in the work you've done through your rehab'," Keeffe said.
In particular, Keeffe says Luke Ball's mentorship was vital.
"Bally was six weeks before me, so I spent a lot of time with him. He's leadership just all round is pretty impressive, so I've been able to learn a few things from him. He's helped me through, and I'd like to think I've helped him through as well," he said.
ACL injuries are becoming more common in the AFL, with 16 suffered last year, and 15 already recorded in 2013.
"It's obviously not good to see," Keeffe said.
"Beforehand you probably didn't worry too much about it, and when you saw it you were like 'oh that's unfortunate', but now you sort of look twice.
"I reckon it would be good to see some sort of research done into why (it happens). There's probably a few people with theories and what-not but obviously I think with the game and it's intensity nowadays and the demands of how quick the game is now has probably contributed somewhat."
Keeffe believes fatigue is a major factor in ACL injuries.
"I'm no physio or no doctor, so I can't really tell but I reckon mine was more a fatigue thing. Mine was late in the fourth quarter of the round nine game against Adelaide last year. Maybe the high intensity, less rests, that kind of stuff. It may be a simple theory that I have, but like I said, I'm no physio, no doctor, no researcher," he said.
Having overcome his knee injury, Keeffe is hoping to break into the senior side once again.
"You put your hand up as soon as possible, but obviously I'm not there yet. Browny (Nathan Brown) and Reidy (Ben Reid) are playing some good footy, so it's going to be hard to get a game," Keeffe said.
