Asked to compare his mood now and at the end of last season, the former world number one added: "It's a big difference".
Beginning on the back nine alongside Richie Ramsay and Pablo Larrazabal, Donaldson birdied two of his opening three holes before following an eagle-three at the 13th with gains at the 17th and 18th.
Fox, playing with Frenchman Gregory Bourdy and Englishman Matthew Southgate, will tee off from the first hole in his second round at 7.40am (4.40pm NZT).
The Welshman would pick his way around the Emirates Golf Club and post a ten under 62, one stroke ahead of English duo Anthony Wall and David Horsey on a day flawless for low scoring in Dubai.
Rory McIlroy is just two shots off the lead after an impressive bogey-free opening round 65 at the Dubai Desert Classic.
Last week's Abu Dhabi HSBC Championship victor Tommy Fleetwood kicked off his week with an opening-round 69, with Danny Willett propping up the leaderboard after posting a triple-bogey and quadruple-bogey over the final two holes of his five-over 77.
The XFL is back, planning on 2020, Vince McMahon says
This will have nothing to do with politics or social issues. "Whatever our rules are will be what our players will abide by". The original XFL distinguished itself from the National Football League by having less rules and more violence.
Horsey finished birdie-birdie to set a blistering pace but has both two-time victor Rory McIlroy (65) and defending champion Sergio Garcia (67) sitting ominously placed on the leaderboard.
At last year's Classic, only Sergio Garcia and Henrik Stenson finished above him on the leaderboard, while Hatton registered a hugely credible top 10 on his previous appearance. "I'm ahead of schedule right now".
"I don't know if it's going to be one, six, two, three or what's going to happen but at least if I feel like I'm getting better, like I keep putting myself in those situations, that's already an achievement and then you try to take as many as you can". I was only thinking of 59, really. "Again, it's a golf course I know how to get around and I know how to shoot good scores on".
"I didn't expect to play as well as I did last week and it's been nice to continue that into this week", said McIlroy, who finished tied for third in Abu Dhabi.
"But from then until now, it completely different". I thought if I could have shot four rounds under par and just saw some good, positive signs in my game, I would have went away happy.