The ending relationship between Scuderia Toro Rosso and Renault Sport has become sour just 2 weeks before the end of the season. Renault's Cyril Abiteboul and Toro Rosso's Franz Tost have made it no secret who they believe is to blame for the situation.
The two men had already had meetings at the previous race at Mexico where only 2 of 6 Renault-powered cars managed to make it to the finish, with the 4 retirements - two of which for Toro Rosso - all attributed to the Renault power unit.
On Friday morning, things went further downhill for Toro Rosso, as the team's cars only completed 7 laps combined, both suffering engine issues. As FP2 went better, the team's comments were still unrevealing.
“Obviously it was a very difficult FP1 for the team again", said Toro Rosso chief race engineer, Jonathan Eddolls.
"We came in knowing we would need to take some engine penalties for MGU-Hs, which we did. Unfortunately, the new MGU-H on Pierre’s car failed early on while the issue on the other car looked more catastrophic than it was. It was something quite simple in the engine, where it smoked badly which everyone saw but we were able to fix it with no further issues."
However, Renault's Cyril Abiteboul made it clear he believed there is something going on at Toro Rosso that causes the numerous failures: "We do have a little bit of concern about the way that our engine is operated in the Toro Rosso car", adding that there are "never coincidencies" in F1.
"It comes as a big surprise to the team that Cyril Abiteboul has suggested to the media that the problems Toro Rosso suffers with the power unit are primarily team related, and the way in which the power unit is operated in the STR12 chassis.
"We would like to clarify that all the MGU-H and Shaft failures Toro Rosso has recently suffered are not associated with how the team is operating or with how the PU is integrated in the chassis.
"Nothing has been changed or altered in this installation during the 2017 season, other than cooling improvements mid-season. Since the summer break Toro Rosso has suffered continuous power unit related failures, and the resulting grid penalties has cost the team points and relative positions in the Constructors’ championship.
"One of the primary reasons for the issues we are seeing is the lack of new power unit parts available. In Toro Rosso’s case the team is constantly having to change parts from one PU to another during the weekend and, on many occasions, is forced to run old specification assemblies."
The team also hinted that their fight with Renault for 6th in the Constructors' championship may have to do with it, but underlined that even though "the situation may not be a coincidence, it is certainly not due to STR’s car".
This subsequently triggered Abiteboul to have a heated discussion with Red Bull's Helmut Marko ahead of Saturday's FP3. The two went on to have another meeting with more Renault bosses after the session to discuss the matter.
Clearly, Renault have little incentive left to uphold a certain reputation with Toro Rosso, given that the team is switching to Honda power units next season. In fact, the troubled situation between Red Bull and Renault since 2014 also triggered Renault to tell Red Bull Racing they were unwilling to supply them beyond 2018, when their current contract ends.