Lewis Hamilton said watching Ferrari and McLaren overhaul Red Bull in the Constructors' Championship has been "quite incredible" ahead of his move to the Italian team.
Red Bull appeared to be set for another dominant year on track after Max Verstappen won seven of the first 10 races, with team-mate Sergio Perez also securing four podiums.
However, Red Bull endured a mid-season struggle, with Verstappen failing to win in 10 races before his stunning wet-weather display at the Brazilian Grand Prix last time out.
The Dutchman is on the cusp of a fourth world championship after title rival Lando Norris could only manage sixth in Interlagos, leaving him 62 points behind in the standings.
But going into the final three races of the season, Red Bull find themselves third in the constructors' championship, 44 points behind leaders McLaren and 13 adrift of Ferrari.
Before Verstappen's victory in Brazil, Ferrari had claimed back-to-back victories in the United States and Mexico.
Charles Leclerc, Hamilton's team-mate for the Scuderia next season, won in Austin to emerge victorious for the eighth time in the competition.
That triumph was then followed up by a win at the Autrodromo Hermanos Rodriguez by Carlos Sainz, who will make way for Hamilton and join Williams next season.
And Ferrari's recent displays on track have Hamilton excited about the potential of challenging for an eighth world championship next season.
"I'm very interested in my future, of course," said Hamilton. "And so, in that respect, keeping an eye, yeah. Watching everything that happens."
"If you look at somewhere like maybe China already, the Red Bull was like a second ahead.
"And it's been quite incredible to see the McLaren rise and then the Ferrari in the last few races, to see their progress and just trying to keep an eye on everyone's car and what they're changing and what they're adding.
"You know, we all watch the video, all the drivers, we all watch the onboard laps and we're always trying to see where we can gain time.
"And there's some cars that just react differently and better or worse in certain areas.
"And you're trying to figure out how you can find that within either your balance or get the team to develop the car in that direction."