Former Manor Formula 1 driver Roberto Merhi is continuing to push for a single-seater race drive in 2016.
The Spaniard contested 13 grands prix last year for Manor, but felt he was never a leading contender to remain with the team this season.
Manor confirmed that GP2 race winner Rio Haryanto had secured the team's remaining seat alongside DTM champion Pascal Wehrlein last Thursday.
"I was not surprised that we couldn't reach a deal to continue with Manor," Merhi told Autosport.
"At the moment I am training very hard to be ready in the event that somebody can offer me a car.
"At this stage of my career, I would definitely prefer to continue in single-seaters, rather than GTs or sportscars.
"I don't think there are opportunities for me in Japan [in Super Formula]. I also can't see myself racing in GP2, as I don't have the budget. Beyond that I can't really say more."
Last season Merhi declared he would rather race in GP3 than take an F1 third driver role that did not offer track time.
Merhi's 2015 Manor team-mate Will Stevens is also yet to announce his racing plans for the forthcoming season.
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