Jenson Button says McLaren hasn't lived up to the team's own expectations, having made the bold claim that their chassis could compete with the best.
The Woking-based outfit often asserted last season that its MCL32 was as good as a Mercedes or a Ferrari but was pinned down by its under-performing Honda engine.
The team's change to Renault this year has undoubtedly improved its fortunes but McLaren is still nowhere near F1's trio of front-runners.
For Button however, his former team should have refrained from creating unrealistic expectations.
"The three big teams, it's difficult to challenge them at the moment and it's going to take a while," Button told Sky News.
"McLaren came out last year and this year and said they think they might have the best car.
It's a tall order to have the best car in Formula 1 when you're racing against Ferrari and Mercedes and Red Bull. And I think we've seen that isn't the case," he added.
"So you'd say the season so far is a disappointment but if they didn't say they had the best car you'd say it's a great season for them.
"They've made good steps, they're fourth in the constructors' standings, but because of what they said at the start of the year you say maybe it's not what we expected."