By Matthew Cooper Christian Horner has admitted Red Bull expect Ferrari to be their “closest competitor” at the upcoming Chinese Grand Prix, following their impressive performance in Suzuka. Both Carlos Sainz and Charles Leclerc made impressive gains as they finished third and fourth respectively at the Japanese Grand Prix earlier this month, with Max Verstappen and Sergio Perez earning Red Bull an impressive 1-2. And Horner unsurprisingly snubbed seven-time world champion Lewis Hamilton when discussing who could rival Red Bull in China, given Mercedes’ poor start to the new season which has s…