Former world champion Fernando Alonso admitted Ferrari have work to do if they are to compete for the Formula One title this season following testing in Barcelona on Wednesday.

Alonso was fourth fastest on the second day of testing, just behind current world champion Sebastian Vettel of Red Bull.

Force India’s Nico Hulkenberg was the surprise pace-setter with Sauber’s Sergio Perez clocking the second fastest time.

“At the moment, we are not where we want to be, nor where we want to be in Australia (for the season-opener on March 18), but I remain optimistic,” said Alonso.

“We still have six days of testing and we will see how it goes.”

However, Alonso insisted that pre-season testing is not always the ideal indicator of genuine pace when the season begins.

“This has been a more laborious winter for us than in the past because we have a more complex car, which features very innovative ideas but that requires greater effort from everyone,” added the Spaniard.

“From the drivers who drive it, the engineers who run and develop it and the mechanics who have to put in over 20-hour days. It’s always nice to have a car that is immediately quick and reliable, but that is not always synonymous with winning.

“Last year, we did a race simulation at the end of the first test and then in Melbourne we were a second and a half off pole position.”

Hulkenberg handed Force India a confidence boost with his fastest lap of one minute and 22.608 seconds from a total of 112 laps on Wednesday.

Vettel, who had been quickest in the morning, finishing third fastest.

Australian Daniel Ricciardo placed fifth, timing 1:23.639 from 49 laps.

Lotus did not test after pulling out on Tuesday due to a chassis problem.

Testing continues until Friday and there will be a final series of testing back in Barcelona on March 1-4, before the teams travel to Australia for the opening race of the season in Melbourne on March 18.