Monte Carlo Rally runner-up Thierry Neuville says he is worried about the "dangerous" pace Toyota showed on last weekend's World Rally Championship season opener.
Hyundai driver Neuville finished runner-up to the Citroen C3 of Sebastien Ogier, but Ott Tanak had led the rally on Thursday evening and was third on Friday until he had to change a tyre on a stage.
That dropped Tanak to seventh, more than two and a half minutes off the lead, but the Toyota driver reeled off six-straight stage wins on Saturday and Sunday morning and recovered to finish third.
Tanak's team-mates Jari-Matti Latvala and Kris Meeke - who won Sunday's powerstage - were fifth and sixth.
Speaking about the Japanese manufacturer's pace, Neuville said: "They are dangerous, we said this before, but we see it again here.
"I hope we have more coming with our car, we are still pushing hard.
"But the speed from Tanak was strong and then Kris [Meeke] on the powerstage - OK, he saved his tyres all day for this, but he was four seconds faster than anybody and six faster than us. That's a lot."
Neuville's concerns were echoed by his new Hyundai team-mate Sebastien Loeb.
The nine-time champion said he was surprised by the speed Tanak showed, but pointed to former Citroen team-mate Meeke's powerstage performance as a cause for real concern.
"We know with Tanak and with Toyota what speed they have," Loeb told Autosport, "but the time with Kris in the powerstage is just incredible."
Meeke won the eight-mile powerstage by 3.9 seconds and Toyotas were fastest or joint-fastest on nine of the rally's 16 stages.
Asked to assess his second Monte Carlo Rally podium in a Toyota, Tanak told Autosport: "I am happy. Things didn't go our way on Friday, but we didn't get stressed by it.
"Since Saturday we did a good job: we were 1m30s behind Jari-Matti and Seb [Loeb], but we still managed to get the podium."
Toyota dominated the second half of last season and was consistently talked up as favourite for 2019.
But team principal Tommi Makinen shrugged off talk of dominating the campaign, saying: "We had some good speed here, but there were some technical issues with [wheel] rims.
"This was only our third time here and we came in different conditions this time.
"OK, we didn't win this one, but the result was very brilliant for us and very brilliant for rallying with three different manufacturers on the podium."