Hopeful Formula One returnee Robert Kubica remains very much in the running for the second Williams seat next season, following two successful tests in a 2014 specification car. With Williams contractually and financially tied in to running 2017 Canadian rookie Lance Stroll in 2018, the most attractive seat left of the grid for next season remains very much open to challenge as the Formula One field head into the final races of the current championship year. It is widely thought that Williams have narrowed down their driver choice to 2017 number one Felipe Massa, reserve driver Paul di Resta, young Mercedes junior driver Pascal Wehrlein and most high profile of all, 2008 Canadian Grand Prix winner and Formula One returnee Robert Kubica. Due to the devastating injuries sustained by the Pole in a rally accident back in 2011, Kubica has long been thought to be out of the running for making a successful comeback to the top level of open wheel motorsport. At 32 years of age, Kubica still has time on his side to achieve some of that lost potential following his big accident back in '11, however questions still remain as to his ultimate fitness ahead of a contract offer from a current Formula One team. The driver looked to be in strong contention for a seat at Renault before the French team opted for Toro Rosso refugee Carlos Sainz to replace the underperforming Jolyon Palmer in Austin, even going so far as to give Kubica seat time in an official Formula One test session in Hungary before electing to go with the young Spanish hotshot. However it appears that Kubica is now in prime position to move over to a recovering Williams team as the Grove concern look to lift themselves from their current performance slump despite running the pace setting Mercedes power unit. Williams have run Kubica in a 2014 specification car at both Silverstone and Hungary in a bid to assess if the driver retains enough fitness to compete next season, labelling the sessions "productive" as they "continue evaluations" ahead of a decision before the end of the current year. Another hopeful returnee, Paul di Resta, will also have the advantage of seat time in the Williams at Hungary as the squad looks to make a decision on what will happen for the 2018 season. With such a rich pool of talent on offer for next year, whoever the team end up choosing to run alongside Stroll could well be in with a shout and bringing around a change in fortunes for this once great team. Check out the Formula One sub forum for more news and discussions from the world of Grand Prix motorsport here at RaceDepartment. Would you like to see Kubica running in the other Williams next season? Who do you think the British team should pick? Let us know in the comments section below!