Naitanui was a star in West Coast's remarkable three-point win over Gold Coast on Saturday afternoon.
The Eagles were 35-points up at three-quarter time in large part because of Naitanui's dominance in the middle.
The 2012 All Australian was playing his 100th match and he celebrated in style with a wonderful display.
He gathered 22 disposals (16 contested), 34 hit-outs, six clearances, had six tackles and was the chief architect of the Eagles' midfield dominance for three quarters.
"He was great," Gaff told AFL.com.au.
"You can see when he's free of all those niggles in the body just what he can do.
"In the first half, he set it on fire.
"It was a big reason why we were so far in front."
Naitanui's ruck work, in the first half particularly, was a work of art. The Eagles had 11 centre clearances to four at half-time for a 21-point lead. Naitanui alone had nine centre hit-outs.
He had 20 hit-outs in total to half-time, including eight to the direct advantage of Eagles teammates.
He also plucked a ball clean out of the ruck in the centre circle, weaved past two opponents, dished a handball to Mark Hutchings who hit Josh Kennedy lace out just before quarter-time, to set-up the second of Kennedy's seven goals.
"We didn't lose a centre bounce clearance for the first half, it didn't feel like," Gaff said.
"It's like having another midfielder in there."
Eagles coach Adam Simpson was also full of praise for Naitanui's performance.
"I just think we're seeing glimpses of his best and for a longer period," Simpson said.
"He's staying in games for longer. He had 22 possessions and had a legitimate impact on the game.
"For a guy who gets criticised a lot for perhaps not understanding how to get the ball, all those sort of things, I think every week I've seen improvement.
Simpson also believed his star ruckman did not get enough credit for knock-ons and taps around the ground that don't register on the stats sheet. Naitanui produced a little tap to Jeremy McGovern to set-up the winning goal in the last quarter that almost went unnoticed.
"Unfortunately you don't get stats for those little knock-ons and hit-ons and efforts that just disrupt the play," Simpson said.
"Because he's so big and strong and powerful, he'd have to have 10 or 15 a game."
