Both Gasly and team-mate Esteban Ocon were eliminated in Q1, qualifying 17th and 18th respectively for the Italian GP.
They didn't fare much better in the race, with Gasly just avoiding being lapped by winner Max Verstappen in 15th, while Ocon's car was retired as a pre-caution after he started encountering a steering lock issue.
While Gasly explained that Alpine had expected to struggle in Monza, that didn't make its weekend any less of a blow.
"It's been super painful," Gasly lamented. "I don't think we have ever had such a lack of competitiveness compared to our rivals.
"We knew straight away from the start of the season that it would be a painful one. But yeah, it was clearly very difficult out there."
Alpine's nadir came just a week on from Gasly scoring a podium in Zandvoort, where the Frenchman outpaced the Ferraris who now battled for the podium themselves.
It provided more evidence of Alpine's trend of struggling on lower downforce circuits, which Gasly hopes the team can understand so its weaknesses can be ironed out for 2024.
Source: Autosport