In the end, it wasn't to be, after a final round where Fox was in the driver's seat on two occasions. Each time Knox responded, with the pair the last ones standing in a round where several players launched bids at the title.
Jorge Campillo's seven-under round saw him leap to 13-under, one shot behind Fox and Knox, defending champion Jon Rahm left his bid too late and finished a further shot back, while Erik Van Rooyen's overnight lead of four strokes soon evaporated, as did his title chances as he too signed for a 12-under total.
At one stage, there were four players tied at 12-under, but Fox pulled away from the pack as part of a back nine birdie binge.
However, after a superb approach at 13 saw him stuff it within three feet for birdie, he found the bunker on the next hole, dropping a shot as Knox knocked one close to tie him atop the leaderboard once more.
It turned into a familiar theme. When Knox couldn't birdie the favourable par-five 17th, Fox struck, hitting the green in two and safely two-putting to take a one-stroke lead into the final hole.
Unfortunately for the 31-year-old, that's when Knox struck. The Scottish world number 87 sunk a mammoth 40-foot putt on 18 to force Fox to require a birdie for victory.
He nearly managed it - a booming drive and delicate approach left Fox needing to hole an eight-footer to win his first title on the European Tour, but past the right edge it skimmed, leaving Fox stunned, and giving Knox a second chance as the pair returned to the 18th hole for a playoff.
There, it was unfortunate deja vu for Fox. A 364 metre bomb of a drive down the middle set him up perfectly, while Knox narrowly avoided a bunker and could only recover to give himself a long putt for birdie.
Somehow, he sunk it again, roaring with delight, sending the crowd into raptures, and leaving Fox with a 12-footer to stay alive.
It lipped out, with Fox having to settle for second, and New Zealand's nine-year drought without a European Tour title continuing.
While missing out on the ultimate goal, Fox did get a handy consolation prize, with his second place finish booking him a spot in the Open Championship - his third appearance in the last four years.
The million dollar pay packet and upcoming rise in the Race to Dubai and World Rankings will be a boon as well, and Fox can see the bright side despite the tough finish.
"I'm happy, and it's a bloody nice consolation to get into the Open Championship."
