The current world champion, Brecel has struggled badly for results since winning snooker's blue riband at the Crucible last spring and he was firmly put in his place on Sunday as Lisowski turned in a terrific display.
The match was all but over at the mid-session interval, Lisowski having raced into a 4-0 lead thanks to breaks of 70, 100, 96 and 69, and though Brecel did stage something of a rally by pulling a couple of frames back, he was unable to turn it into a serious comeback.
A poor opening frame from Brecel which featured a number of early mistakes set the tone for the afternoon and frame three was very similar, the Belgian in first with 28 before going in-off and allowing Lisowski to clear the table.
Brecel's brief fightback after the break came via runs of 95 and 103 as Lisowski only managed four points across the two frames, but his game held together throughout and he put the match to bed in ruthless fashion.
A break of 63 broke the back of the seventh frame, moving him 5-3 ahead, before he signed off with a well-taken 68 to set up a quarter-final meeting with Shaun Murphy.
Lisowski told the BBC afterwards: "I felt great. You never know what it’s going to be like coming out here. I started well straight away and felt like I couldn’t miss.
"I think I found something in China. Thank God, because I was really struggling.
"I was really scared to come here today, to be honest, because I didn’t know what Jack was going to turn up. I felt great, so I think something happened in China."
Brecel was left a frustrated figure following another disappointing early exit and told World Snooker Tour: "It was terrible. If I keep playing like this then you will see me in 2025 Q School.
"I can recapture the form and I know I will, but at the moment it is just not good enough."
Murphy eases past Zhang
Murphy made relatively light work of Zhang Anda, winning 6-2 after landing a couple of body blows on his opponent early in the match.
Murphy reeled off five fifty-plus breaks, but the most important of them came in frame four when overturning a 61-point deficit to pinch the frame with a fabulous clearance of 65.
That allowed the 2015 champion to lead 3-1 at the mid-session interval and he was able to keep Zhang, who was making his Masters debut this year, at arms length thereafter.
When Zhang broke down in frame seven, Murphy once again made him pay with a break of 71 and he put the match to bed soon after, finishing with a flourish and a run of 89.
"I am really pleased, because I felt towards the back end of 2023 my game was sort of on the tilt a bit, I wasn’t getting the results, but I worked really hard over the festive period," Murphy said.
"That is unlike me, because I would normally kind of put the cue down and not play. It was so rewarding, regardless of what else happens this week, to see that come out when it mattered the most."
Murphy added on Eurosport: "I felt as if maybe I wasn’t quite putting enough time in on my own, so maybe that was the first place to look.
"I decided when I was back in Dublin I wouldn’t go out all the time and not get involved in the parties, the Christmas spirit and all the rest of it, and (instead) that I would get stuck in on the table.
"Even though my club in St Stephen’s Green was closed, they gave me the secret key and I was in there grafting."
Sunday's Masters schedule
Afternoon session (1300 GMT)
- Luca Brecel 2-6 Jack Lisowski
Evening session (1900 GMT)
- Shaun Murphy 6-2 Zhang Anda
Fast Results
Scores
Racecards 
