Christian Klien insists that he still has a chance of returning to the F1 grid this season, despite appearing to be on the outside looking in after others tested with HRT last month.

The Austrian completed the 2010 season with the team but has so far been excluded from driving during the three winter test sessions as HRT focused on getting F1 returnee Narain Karthikeyan up to speed before giving fellow hopefuls Tonio Liuzzi and Giorgio Mondini a run-out at Barcelona in February. While Karthikeyan remains the only confirmed driver in Colin Kolles' line-up, Klien believes he still has a chance to see off his rivals with just a handful of weeks remaining to the start of the season.

While Spanish newspaper AS lists former Toro Rosso and Force India driver Liuzzi as favourite to land the one remaining seat on the grid, the Austrian - another product of the Red Bull stable - told his personal website that missing testing was not necessarily a sign that his hopes were over.

"All [winter] tests were done with the 2010 car, which I raced on five weekends last season [and], together with the race engineers, I did a lot of set-up work on it to improve performance," he reasoned, "At the end of the season, we were able to close the gap to the other teams, although there was not a single new part all year long. Other drivers like Tonio or Giorgio Mondini have no experience in this car [but], from a team's perspective, it is only justified to get as much feedback as possible and test other drivers' work.

"[However], my manager is in permanent contact with the team's management [and], needless to say, I would love to drive for HRT. F1 is still fun [even at the back of the field]. It is the highest privilege a racing driver can earn himself. Who loses the ambition when good results don't come easy may just as well go looking for another job."

With HRT finally due to introduce its 2011 car at this week's final group test in Barcelona, the team will effectively be starting from scratch in the development race, but Klien is adamant that the small Spanish team has the capability to surprise.

"Wait and see! Premature forecasts can sometimes be wrong," he claimed, "Each day matters but, if you look back at how this team rose from the ashes of another operation at the beginning of 2010, you will have no doubt HRT will make the most of its limited resources in 2011. They have a solid and analytical way of facing challenges.

"I am convinced the team will make good progress and surprise a few people. In Geoff Willis and chief designer Paul White, they have engineers who know very well how to build competitive racing cars - and they are masters of efficiency like no other team on the grid."

Although he admits that he is unable to bring as much sponsorship as some other drivers to have been linked to the HRT vacancy, Klien does not believe that he is up against true 'pay drivers' for the seat, and insists that he is confident enough to have poured all his energies into securing an F1 ride for 2011.

"F1's economic situation has changed dramatically," he pointed out, "The top flight teams still have good sources of income but, once you go down to the midfield teams, everyone seems to be struggling for cash. In all my years in F1 and sportscars, I have never paid for a seat, but I was paid for my services - and this is how it will remain in the future. But, then again, there are hardly any real pay drivers. A pay driver digs into his very own pocket. All others bring their sponsors and partners onto the market place. This is how it works for about two thirds of the current field.

"Currently my focus is on F1 only. The only alternative to the seat at HRT would be a third driver role with a clear perspective of a race seat some time soon. If neither works out, you will certainly find me racing elsewhere. There are many interesting international series which offer a high level of professionalism, technological challenges and many miles in the car. Luckily, once you have established yourself as a driver in F1 the door to other series is always open."

The Spanish media, meanwhile, remains convinced that Liuzzi will eventually prevail over both Klien and the more improbable Mondini.

"The last details are still missing, but the agreement between Hispania and Liuzzi is about to be formalised," the AS report insisted.