Sergey Sirotkin says he feels "really sorry" for the struggles his previous Williams team faced amid a trying first week of pre-season testing, and the Russian says he has no ill feeling towards his former colleagues and hopes they "get what they deserve".
Williams missed the first two-and-a-half days of last week's test due to difficulties getting the FW42 built, although George Russell delivered an impressive 119 laps on day one of test two in Barcelona.
Speaking in Barcelona following his confirmation as Renault's test driver for 2019, Sirotkin sympathised with his former employers and said that despite only spending a single season with the them, he feels like he had been with Williams "forever".
"We all know [Williams] is in a very difficult position, but at the same time, I have so many great friends there, so many great people," said Sirotkin.
"I know that we only spent a season together but it's a very long year and we spent so many days together at the factory, together at race tracks, all along working together in such a difficult situation so it really feels like I was there forever.
Behold our full driver line-up for the 2019 @F1 season!
Nico & Daniel will be joined by @sirotkin_sergey as Third & Reserve Driver, with @JaitkenRacer as Test Driver. The quartet will be complemented by Development Driver @gyzhou_33.
"I really feel sorry for them," he added. "I know how much work we altogether put into development and I feel really sorry because of certain difficulties they will not see that as a result in terms of performance.
"I know the people there and what they deserve, so I just want to wish them all the best and really hope that they will get what they really deserve."
Sirotkin, who spent two years as Renault's test and development driver between 2016-2017, explained that he sees his role this season as an "interesting step backwards" from racing, but remains focused on securing a return to F1 in 2020.
"It's still quite early to say now [if an F1 return is possible] but I really try to consider this as a little interesting step backwards to get ready for the big jump ahead. I really hope that's [not too] optimistic, but it's my realistic plan," said Sirotkin.
Following his departure from F1 at the end of last season, Sirotkin has secured a race deal in the World Endurance Championship, and also took the opportunity to test a Mahindra Formula E car last month in Marrakesh.
The Russian says his Formula E experience was of particular interest and he now sees the all-electric series as potential destination if a return to the F1 grid does not work out.
"I really enjoyed [the Formula E test] to be honest. I was honestly never a fan of the series before, but those two weeks I worked around that project, doing the testing and some analysis after that, it really changed my opinion the opposite way around," said Sirotkin.
"I left Marrakesh with a really strong impression of how actually good the car is, and how much fun it is to drive and how good [Formula E] is as a series. I mean, honestly, I was quite impressed so potentially it's a future [option for me].
"The priority is to be back here on the F1 grid but if we see that's not going to be possible anymore, it's a great championship and [could be] a great place for me to be."