Daniel Ricciardo says it would be "naive'' to rule out Mercedes and Ferrari from challenging for pole position in Mexico after Formula One's two leading teams struggled to match the impressive pace of Red Bull in Friday practice for the Mexican Grand Prix.
Red Bull ended Friday's two practice sessions at the Autodromo Hermanos Rodriguez fastest, with Max Verstappen leading Ricciardo in both sessions. Red Bull was over 1.2s clear of the rest of the field, which was led by the Renault of Carlos Sainz.
Despite enjoying a sizeable advantage over Mercedes and Ferrari in practice, Ricciardo expects both teams to be back on form on Saturday.
"If it stays like this, then yeah, it's between us two, but I don't want to be naïve,'' Ricciardo said. "I'm sure Ferrari and Mercedes will come on strong tomorrow. We'll see what happens. I hope they don't. it could be a close six-way fight for pole. I think that would be pretty exciting.''
While Ricciardo is satisfied with his own performance over one-lap, the Australian admits work needs to be done to improve his race pace if he is to end his podium drought -- having not finished in the top three since winning the Monaco Grand Prix in May.
"I was happy with the low-fuel performance, it was much closer to the pace,'' Ricciardo added. "The high fuel we seemed off the pace. I could feel the car wasn't quite there but we were still more off the pace than we probably though. We'll work on the high fuel, but the low fuel for now doesn't seem too bad.''