Ominous Alcaraz 'really, really happy' with Australian Open form
The Spanish third seed showed no mercy to Japan's Yoshihito Nishioka, who was taught a 6-0, 6-1, 6-4 lesson on Margaret Court Arena in an 81-minute rout.
"I think I played really solid today," said Alcaraz, who won Roland Garros and Wimbledon last year but is yet to go beyond the quarter-finals at Melbourne Park.
"I improved the things that I had to improve from the first match. Just really, really happy with everything today.
"An important win for me. Three straight sets with a really high level. Hopefully continue like this."
Alcaraz tweaked his serve in the off-season and is in Melbourne with a lighter racquet, with the dividends evident.
He fired down 14 aces and won 89 percent of his first-serve points.
"I'm really happy with the serve today. It's something I worked on in the pre-season," he said.
"In the first round I struggled a bit. But I spent more time yesterday practising my serve, it's something I really want to be better.
"I'm really glad that today it worked pretty well and hopefully in the next round it's going to be better."
Alcaraz is bidding to become the youngest men's winner in Australia since Novak Djokovic won the first of his 10 titles in 2008.
Should he do so, he will also be the youngest man to complete a career Grand Slam, with his sizzling form so far boding well for the 21-year-old.
He eased through his first-round match in straight sets and came out firing against the 65th-ranked Nishioka.
The Japanese player could barely get his racquet on the ball in the first set, winning just two from 16 points at the baseline and only four points in the entire set.
Alcaraz pounded down five aces in the second set and won a formidable 91 percent on first serve to give Nishioka no chance.
The Japanese player did his best to make a match of it in the third set, but the gulf in class was too wide with the win a formality.
"The less time you spend on court in the Grand Slams, especially in the beginning, it is going to be better," added Alcaraz,
"Physically I'm feeling great and I was just focused with spending as little time as I can on court."
He will next play Portugal's Nuno Borges, who beat Australia's Jordan Thompson 6-3, 6-2, 6-4.