LONDON, England - 2013 Formula 1 champion team Red Bull believes it can pick up the pace and take the fight to 2014-dominant Mercedes now that racing is heading back to Europe.Team principal Christian Horner kept calm after Mercedes chalked up its fourth win from four races, including a third 1-2 and a hat trick for Lewis Hamilton.'GIVE IT EVERYTHING'Horner, whose team has only one podium finish so far this year, told Sky Sports TV: "If we are going to make a championship of it, we've got to take the fight to them. We're going to give it everything, we just can't concede too much more ground."We were 22km/h slower on that (Shanghai) kilometre straight. That's almost 100m that we're giving away. That's where we've got to improve. We know where we've got to fix our issues and I hope there's some steps towards that in Barcelona."That's the Spanish GP on May 11 in Barcelona where all the teams are sure to bring upgrades after the three-week break.Red Bull's design wizard Adrian Newey skipped Shanghai to work on improvements and his rivals need no reminding about his reputation.Niki Lauda, non-executive chairman of the Mercedes team, warned after the Shanghai race: "The Red Bulls are famous for coming back and Newey is there. He wasn't here so he sends something new for Barcelona, I'm afraid."Australian Daniel Ricciardo was fourth for Red Bull in China, with quadruple champion Vettel fifth after being ordered to move aside for his younger team mate for the second race in a row. The German did so, but reluctantly.Horner had only praise for the youngster, who has had the better of Vettel in three races. "He's just Joe Cool, isn't he? He's always smiling," Horner said of the Australian. "And he's quick. We knew he was quick but he's exceeded all our expectations."He's so cool under pressure. I don't know whether you hear any of his radio but it's like he's having a chat at a coffee bar. You wouldn't think he's in a GP."He's been enormously impressive since the start of the season in Melbourne. His confidence is growing, you can see that."VETTEL WILL BE BACKRicciardo has out-qualified Vettel three times but Horner said the German would fight back. "We know Seb is very sensitive to the car, how it enters a corner, and at the moment he hasn't the feel he needs from the car."As soon as he gets on top of that, bang. He'll be right back."Vettel, winner of nine races in a row at the end of 2013, has made slow starts previously yet still come out on top but he's facing his biggest challenge yet. The new Mercedes 'power unit' has been the pick of the grid while Red Bull's partner Renault is still playing catch-up.Although Red Bull has now clawed its way back to second in the Constructors' standings the team is still 97 points behind Mercedes. Vettel is fifth in the Drivers' championship, 46 points behind Mercedes' Nico Rosberg.Horner said of Vettel: "He's a deep thinker, he'll analyse this. One thing he does incredibly well is look inwardly at where he can improve, where can he be better, what is the other guy doing that's giving him that advantage?"Sebastian is an absolute fighter and we've seen that before... we'll sit down and talk it through but he won't need motivating, that's for sure."Stay with Wheels24 for the 2014 F1 season – fresh reports every day.