Sergio Perez has revealed where he believes the tide began to turn on his F1 championship challenge.
Red Bull teammate Max Verstappen has dominated proceedings this season and has the chance to secure his third consecutive World Championship during the Sprint race at the Qatar Grand Prix this weekend.
Perez had been challenging for the Drivers' title early in the season having won two of the first four races in fine style, only for a rough patch of form quickly taking him out of contention.
In the same period, Verstappen put together a record run of races won in a row to assert himself over the chasing pack and speaking to media including RacingNews365.com, Perez conceded: "Max has done a tremendous job and no credit should be taken away from the season he has done.
"He has driven on another level compared to anyone and that is something I have a lot of respect for."
Barcelona turning point
Despite the team's dominance and a development penalty for its 2021 budget cap breach, Red Bull has continuously added performance improvements to stay ahead of rivals.
But these have often taken the RB19 away from Perez's comfort zone and highlighting where he felt his control slipping away, the Mexican explained: "From my side, I feel like Barcelona was quite a turning point.
"I was always chasing the weekend more and sometimes, you have weekends where things come more naturally and you are two or three steps ahead.
"I feel since Barcelona, I was starting to struggle and have some deficits with the car."