Alonso has proved to be one of the stars of the 2023 campaign after bagging six podiums, while Stroll has endured a more challenging time with his best result being fourth place at the crash-hit Australian GP.
And although Stroll has singled out Alonso as the "best team-mate" he has ever had in F1, he says that is no excuse for not lifting his own performances to try to match him.
"In terms of just outright pace, he's been more on top of it than me," admitted Stroll ahead of the Austrian Grand Prix. "He's been quicker, and he's been driving incredibly well.
"I don't think we, as a team, have gotten the most out of our weekends. I think we haven't shown some of our true results but there's definitely some work to do, and some things to improve.
"Fernando has been at a very, very high level, and I've got to definitely work on a few things and get better."
Stroll believes many factors have come together to contribute to the difficulties he has faced, but has admitted that even on his good days Alonso has still had an edge.
"I think it's a combination of things," he said. "I think things from the car you're always looking for, and things from me. I missed a tremendous amount of testing at the beginning of the season, and that's always a big thing.
"But honestly Fernando has just been at a really, really high level. And even when I felt like some of my best days were really good days, he's been that a little bit quicker. He's been at a really high level."
Source: Autosport