The 19-year-old made 54, becoming the first Pakistan batsman to score a half-century in his T20I debut
Australia coach Justin Langer praised Pakistan's "fantastic" Haider Ali after the teenager marked his international debut with a sparkling fifty against England.
The 19-year-old made 54, becoming the first Pakistan batsman to score a half-century in his first Twenty20 international as the tourists beat England by five runs in a last-ball thriller in Manchester on Tuesday.
Haider came in with Pakistan 2-1 after the loss of Fakhar Zaman at Old Trafford yet struck his second ball in international cricket, from off-spinner Moeen Ali, for a soaring six.
"He's fantastic," said Langer in a conference call Wednesday from Southampton, where Australia begin a three-match Twenty20 series of their own against England later this week.
"Pakistan as we've always known, they are like a sleeping giant. They've got so much talent, it's like India, it's exciting to watch."
Pakistan's tour-ending victory meant the three-match T20 series finished all square at 1-1, with one rain-marred no result.
The game was also notable for a stand of exactly 100 between Haider and 39-year-old veteran all-rounder Mohammad Hafeez, who made an unbeaten 86.
Asked if he had ever been involved in a partnership featuring a similar age gap, former Australia opening batsman Langer replied: "My experience of that was with Shaun Marsh.
"I've known him since he was born. Geoff Marsh (Shaun's father) and Michelle, they are great friends of mine. Geoff was my first captain.
"We played together when he was 17 or 18 for Western Australia. I understand that experience for the Pakistanis last night. It's great to see these young kids come in and play.
"He (Haider) hit a six off his second ball in international cricket, it's exciting to watch."