Mercedes are "really on the limit" with their engines as a result of the pressure applied by rivals Max Verstappen and Red Bull throughout the 2021 F1 season, reckons Dutch racing driver Tim Coronel.
Mercedes have introduced several new engines in recent weeks, amid reliability concerns, with Lewis Hamilton on his fourth ICE (Internal Combustion Engine) of the season and teammate Valtteri Bottas running a sixth.
Verstappen moved on to a fourth new Honda engine (as part of a complete power unit change) slightly earlier in the season in Russia, but team boss Christian Horner is hopeful that no further changes will be required on their side.
Coronel, a Dakar Rally regular who also previously competed in the World Touring Car Championship, expressed surprise about Mercedes' recent spate of changes and reckons they are simply acting to avoid a DNF.
"I didn't expect it and look at it with surprise!" Coronel told RacingNews365.com in an exclusive interview.
"Apparently, Mercedes is really on the limit, otherwise they wouldn't make these decisions. They don't dare to take the risk that the season might be decided by a misfiring engine."
At the same time, Coronel feels that Verstappen and Red Bull can gain an advantage from the situation.
"It forms an opportunity for them," he added. "Of course, Verstappen and Red Bull are also indirectly the cause of those problems, because they are putting so much pressure on Mercedes now."
Coronel sees another advantage for Verstappen with the return of Adrian Newey following a cycling accident.
"It always matters when someone like that is not there," said Coronel. "If he is there, then he gets sucked in and extra i's are dotted.
"I'm glad he's back, even if it's just the feeling. I don't think Adrian is missing anything in that area, so it's nice for Verstappen to have him here. Whether it can be a decisive factor in the title fight? I don't know."
After an intriguing strategic battle last time out in the United States, Coronel stressed that Verstappen and Hamilton will have to rely on their teams performing to the maximum over the final five races of the season.
He also expressed caution over predictions that Red Bull are firm favourites for Mexico and Brazil.
"Last weekend, we said the same about Mercedes!" Coronel stated. "It has now become a battle between the teams, not just between the drivers. Who will respond best to what Red Bull did last weekend? It will be a battle of reaction."
Verstappen leads Hamilton by 12 points in the Drivers' standings.
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