Former Red Bull driver Mark Webber has turned the heat up on McLaren Honda as Fernando Alonso enters what could be the final five months of his stint with the struggling team.
Alonso has not finished in the top 10 in his six races this year, with the two-time Formula One champion reaching the chequered flag just once among a season of two retirements, two classified DNFs and one DNS.
The Spaniard has engaged in a verbal war with his car, even going as far as sitting out the famed Monaco Grand Prix for his first attempt at the Indy 500 last month.
Alonso's contract with McLaren expires at the end of the season, with the 35-year-old open about his desire to leave for a challenger.
"It goes in cycles with drivers," Webber told Yahoo7 during his weekend in Italy with Red Bull for the World Rally Championship.
"You can find yourself in a situation with a team where operationally or reliability-wise it's clearly a challenge. Fernando's in that window right now unfortunately.
"For a man of such colossal talent it's absolutely criminal that he's in that situation, but that's the way it is. McLaren and Honda are in a tricky situation so for him his reliability and finishing rate is clearly a disaster."
For their part, McLaren officials haven't hidden their frustration with engine manufacturer Honda since the partnership began with the 2015 season.
Alonso's most recent car troubles, in Canada, were described as 'gut-wrenching' by racing director Eric Boullier, who said: "It's difficult to find the right words to express our disappointment, our frustration and, yes, our sadness. So I'll say only this. It's simply, and absolutely, not good enough."
Speculation has whispered through the F1 paddock in recent weeks that the Woking-based team is weighing up whether to link with Mercedes for a second run with the German company's power units.
While that plays out in the background, Alonso has fought on and impressed Webber with his performances in spite of the troubled car and his future with the team.
"It's nothing that he can control so he's just got to keep his head down and work as hard as he can, which he's doing," the Australian said.
"I think his mindset is totally in the right place at the moment. He's probably already made his decision, so that'll be interesting to see when it comes out."
Webber's comments come just days after Williams driver Felipe Massa, who spent four years as Alonso's teammate at Ferrari, said the Spaniard should consider quitting F1 for good.
"I think if you're not having a good time, it's best to leave," the Brazilian said.
"He does not seem to be enjoying much right now, so maybe he will. Maybe he will go to another team or take on other challenges outside of Formula One."
Massa's remarkable suggestion can't be ignored, given he retired from the sport at the end of last year before being asked to fill the seat vacated by ex-teammate and Mercedes recruit Valtteri Bottas.
While he could have felt finished at the top level and rejected Williams' offer, Massa has instead returned and driven well for four top-10 finishes in the first seven races.
It is that kind of turnaround that, according to Webber, should continue to motivate Alonso for the rest of the season and potentially into a contract with another team.
"Fernando Alonso is on the podium all day long if he's in the right car, if not the middle step. He's challenging for victories," Webber mused.
"He hasn't lost his talent overnight and he's done some phenomenal drives this year in a very, very mediocre car."