Piastri was second fastest in qualifying behind Charles Leclerc, missing out to the Ferrari driver by 0.154s.
“On the whole I’m very happy with it,” Piastri said of his qualifying hour.
“We were struggling a little bit through the weekend. We didn’t really know quite where we sat.”
Piastri didn’t complete a soft tyre run in Free Practice 2 on Friday, which left him down the order after an especially competitive opening day.
He was then fourth fastest in Saturday morning’s practice hour, though half a second back from Leclerc, who topped proceedings.
“A bit of work to do after FP3, but the car felt very good in qualifying,” Piastri admitted.
“I think the last lap of Q3, there’s a few corners I wish I could have again, but when you’re pushing so hard, it’s kind of inevitable that there’s going to be mistakes here and there.
“Turn 5 and Turn 10, the chicane after the tunnel, were not my best,” he admitted.
“I think the rest of the lap was pretty solid. Just, yeah, struggled a little bit in those two corners.
“Whether it would have been enough for pole, I’m not sure.”
Piastri had demonstrated good pace throughout the session, and was even faster than Leclerc in Qualifying 2 before falling a tenth short in the all-important Qualifying 3.
“The pace in the car was good, and I think for Monaco qualifying it went reasonably smoothly,” he added.
“I hit the wall pretty hard in Q2, so that was a bit of a scare, but apart from that, it was a smooth qualifying.
“I’m happy to be on the front row and hopefully staying on the front row this week.
It’s the second successive event where the Australian has recorded a time good enough for the front row after he was second quickest in Imola last weekend, where a grid penalty left him fifth.
There are no such issues this weekend with the front-row berth capping off the day for the 23-year-old.
“Monaco qualifying is the most exciting session of the whole year,” he admitted.
“For us as drivers, I think for the fans watching… Yeah, I think if there’s one session you want to watch for the whole year, it’s the session we just had.
“For me, it gives you a feeling like nowhere else, especially when you put a good lap together.
“It’s very, very satisfying here.”
The Monaco Grand Prix begins at 15:00 local time on Sunday (23:00 AEST).