Considering Mace as of like 60 was one of the best duelists in the Order's history, and so is 80 year old Dooku, and, nearly 900 year old Yoda...
TPM novel can go swing, lul.
Anyway, from what I remember, Qui-Gon did nothing but die at Maul's hands and spar with but never actually beat Mace 20 years prior to Return of the Sith.
So he loses. 😐
Well, look at Kenobi in ANH, obviously they didn't all age the same. 3 different paragraphs. Kinda hard to argue with.
Pg. 283: "Qui-Gon was nearing sixty; his youth was behind him and his strength was beginning to diminish."
Pg 286: "He was worn and battered by now, close to exhaustion..."
Pg 299: "Obi wan did not like the weariness he saw in the slump of the older man's shoulders, in the bow of his back. He was the best swordsman Obi-Wan had ever seen, but he was growing old"
Pg 200: "His opponent was strong, and had tested him severely. He was getting old, he decided, and he did not like the feeling."
Without question, TPM QGJ was not at his peak.