Given the nod to start by Giancarlo Italiano after an error from English import Josh Oluwayemi led to Adelaide's late winner over the Phoenix last Saturday, the 19-year-old produced several sharp saves as his side secured a point that moved them out of the bottom four.
Entering the contest as the league's highest-scoring side, the Sky Blues huffed and puffed across the 90 minutes but proved unable to break through a stubborn Phoenix side that offered enough in transition to keep the visitors from going all out on attack.
"I thought (Kelly-Heald) was brilliant, I don't think he put a foot wrong all game," Wootton told Sky Sport NZ.
"His distribution was spot on. Any saves he had to make he made."
In Ufuk Talay's first visit to Sky Stadium since leaving the Phoenix managerial role, his side outshot the hosts 19 to five and had 34 touches in the opposition's penalty area compared to seven but lacked a lethal edge.
"We haven't had one in a long, long time, so that's a huge positive," Wootton said of the clean sheet.
"Never really felt too threatened. They've got a lot of really good attacking players and I thought for most of the game we dealt with them."
Though missing the chance to move into the league's top three, it was the third clean sheet in the Sky Blues' six-game unbeaten run and their first on the road in 2024-25 - in sharp contrast with the leaky defence that hampered their early-season efforts.
Polish striker Patryk Klimala led the way, a flurry at the end of the first-half giving them momentum heading into the break.
The Phoenix suffered a blow soon after play resumed when Sam Sutton was forced off after turning his ankle.
But the hosts held firm, with VAR coming to their aid in the 70th minute when a penalty initially awarded against Isaac Hughes was overturned.
Leo Sena was also booked for simulation by referee Shaun Evans when he went down appealing for a spot kick six minutes later.
"(The overturned penalty) looked like he might have got a little bit of ball, just a matter if you got the guy with him," Sydney captain Rhyan Grant told Sky Sport NZ.
