LONDON, England - Ferrari's Fernando Alonso needs to make the most of his home advantage when F1's European season opens in Barcelona on Sunday.The Spaniard has ground to make up on Red Bull's triple champion Sebastian Vettel after four races in Asia and the Middle East."If I was to score our overall performance, I would only give it a six out of 10," Ferrari chief designer Nikolas Tombazis has said. "We are not quite where we want to be. In the first four grands prix we were not really able to fight for pole position - that's one of our main objectives now"NEW DEVELOPMENTSThe days when Alonso could count on the emotional boost of two home grands prix are gone. He won in Valencia in 2012 but that race is now off the 2013 calendar so he needs a podium finish t the Circuit de Catalunya.This time a year earlier Alonso arrived in Barcelona 10 points behind World champion Vettel for a battle that ultimately went down to the wire in the German's favour. Already, despite Ferrari having a much more competitive car and Alonso winning in China, the gap to Vettel is 30 points and all the top teams are bringing new developments to the track now that they are back in Europe.Alonso retired in Malaysia in March after losing his car's front wing when he tagged Vettel at the start and finished only eighth in Bahrain in April when his rear wing DRS system failed to function. That problem has been solved and Ferrari have updates to the bodywork, floor and wings.There are more questions than answers at this stage of the season and McLaren, a frequent title-challenging team which ended 2012 with the fastest car but started 2013 well off the pace, has plenty to deal with.McLaren's 2009 champion Jenson Button, previewing the race, said: "I think returning to a circuit where we undertook two of the pre-season tests will give us a useful benchmark of our progress. I'm pragmatic about what we'll discover (at Catalunya). I hope it'll move us a step closer towards the destination."'GOING TO BE HARD'Vettel has already won twice in 2013 and his form in Bahrain looked ominous. Stopping that momentum is the big challenge for other teams. Kimi Raikkonen, now second overall for Lotus and seeking his 22nd consecutive points finish this weekend, is 10 points behind and only too aware of what needs to be done."It's going to be hard to catch Sebastian if he keeps taking good results so we need to start taking more points from him," said the Finn. "It's no secret that we want more speed from the car in qualifying. It's so tight up there at the front and we really need to be on the first two rows to fight for victories every time."That is more than ever the case in Barcelona, where 18 of the previous 22 winners started on pole and only one driver - now-retired Michael Schumacher - has ever won from anywhere other than the front row.Venezuelan Pastor Maldonado won in 2012 for Williams, the team's first GP success in nearly eight years, but lightning is unlikely to strike twice with the former World champions still chasing their first point of 2013. The team's Finnish rookie Valtteri Bottas said: "Following a good aero test last week at Idiada (Spain) and a number of upgrades I hope Barcelona will be the start of improved performance for us."