The team experimented further with set-up options in Free Practice Three, but could not make it further than the first segment of qualifying.
However, grid penalties for multiple drivers elevate both Sebastian and Lance up the grid for race day.
Sebastian started his Saturday running by scrubbing in a few sets of tyres at the start of FP3, before switching to the Soft compound for the remainder of the session.
His best time was a 1.23.104, putting him 17th overall after 20 laps.
Sebastian went out on a new set of Soft tyres at the start of qualifying, putting in an early marker of 1.23.919.
Plenty of laps on the opening day at Monza
Aston Martin Aramco Cognizant Formula One™ Team completed over 100 laps on the first day of the Italian Grand Prix weekend, with Nyck de Vries turning his first laps behind the wheel of the AMR22.
His session was interrupted by a loose blanking panel, which required him to return to the garage for repairs before being released onto the track in time for the final qualifying runs.
He put in a time of 1.22.636, but this would only secure 17th position and he did not progress beyond Q1, narrowly missing the cut.
Penalties for multiple drivers mean that Sebastian will start the race in 11th position.
"I was happy with the lap that I did today, which was a reasonable effort from my side.
"I only had one attempt in the end because of the bodywork coming loose during the first run, which meant that I was unable to get into a rhythm.
"Generally, this weekend has not been easy for us. At this track, for some reason, we are just not particularly competitive.
"But it is a new day tomorrow and we will push hard to make progress. We will gain some grid positions from others taking penalties, so we should start in the middle of the grid.
"We are usually more competitive on Sundays so let us see what we can achieve tomorrow."
Lance's FP3 started with scrubbing in sets of tyres, before he switched to the Soft tyres for the rest of the hour of running.
He completed 16 laps and finished 20th, with a best time of 1.23.739 on the board.
Lance did three Soft-tyre runs during Q1, and the first of his fast laps was a 1.24.231. He improved on his second effort to set a 1.22.997.
His last run culminated in his best lap of the session – a 1.22.748, placing him 18th in the order and ending his qualifying efforts.
Penalties for several drivers ahead mean that he will start the race from 12th on the grid.
"We always knew that this would not be our strongest track and I think that showed with today's result.
"Monza is a very different circuit to the tracks we have visited recently, so hopefully this is a bit of an outlier. We seem to have a bit too much drag on the car for this high-speed circuit.
"I am sure we will have stronger performances later on in the season. We will gain grid positions through other drivers taking penalties, so things could work out better for us tomorrow.
"We will try and do what we can to race for points tomorrow."
Mike Krack, Team Principal
"Sebastian's qualifying session was complicated by a loose blanking panel, which cost him some track time when we took the precaution to box him and remedy the issue. He made it out for a final run and ended up just seven hundredths off making Q2.
"Lance had a clean and tidy session, sticking to the run plan, but the circuit characteristics of Monza are not especially suited to our car and it was always going to be a challenging qualifying session.
"I am more optimistic for our race performance tomorrow and we expect to gain a handful of grid positions when other drivers take grid drops due to penalties."
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