Sergio Perez expressed his shock at McLaren's decision to drop him on Thursday and hoped he would find another Formula One drive for next season despite time being against him.
The Mexican, who has two more races with the team including Sunday's U.S. Grand Prix, recognised he was entering a crowded market place.
The 23-year-old, who is to be replaced by Danish rookie Kevin Magnussen, said he was told only days ago that he was being cut loose.
"I found out only a couple of days before you," a composed Perez told reporters. "I had no idea. It came as a shock to me because the team was always giving good feedback to me.
"Everything was pretty much settled down and I was going to stay with the team but then something happened in the last few weeks and they decided not to, so it puts me in a very difficult position now to move forward for my future."
Perez had issued a statement on Wednesday confirming he would be leaving McLaren after just one year, the former champions' worst season since 1980.
Neither he nor his team mate, Britain's 2009 world champion Jenson Button, have finished higher than fifth in 17 races so far.
Perez's position had looked safe, with McLaren seemingly prepared to give him the benefit of the doubt, until last month when momentum began to build behind Renault 3.5 world series champion Magnussen.
McLaren confirmed in a statement on Thursday that the Dane, son of former F1 racer Jan, would replace the Mexican alongside Button.
"The year we had was so disappointing for everyone, they had to do some changes and they have to change me. That's racing," shrugged Perez.
"McLaren decided another route and I have to find my own route and hopefully I can find as good as possible a seat available.
"I am only 23 years old and have a lot to give to the sport and I really hope I find a good seat," he said.
Perez faces competition for those that are still open, with well-funded Venezuelan Pastor Maldonado linked to Lotus, Sauber and Force India while Germany's Nico Hulkenberg is a highly-rated prospect.
Only Lotus among the top four teams have a vacancy but they are waiting to see whether long-awaited new investment comes through before making a decision.
"It's no secret it is very tough right now," said Perez.
"I know there are some options and I want to stay in Formula One but won't just stay if I don't find the right option for myself. I will have to look at something else but I am pretty confident something will happen.
"Everything came very late which puts me in a very difficult position for my future."