Since his arrival in Enstone, Kimi Raikkonen has been gradually winning over his team and giving them the motivational boost that was sorely missed after Robert Kubica's tragic rallying accident prior to the start of the 2011 season.

"After the frustrations of 2011 and the loss of the model that we had built around Robert, the arrival of Kimi has been the secret to the galvanisation of the team. It has been a big boost," said Lotus team principal Eric Boullier, in an interview with Autosport.

According to Boullier, Raikkonen's presence and demeanour within the team has demonstrated that the Finn is capable of being the team leader, although not in the same mould of Kubica.

"Every driver is different and has their own character. Kimi is bringing a different kind of leadership to Robert. Firstly, there is his record. He has been the world champion but by being very clear and very consistent in what he wants, he has imposed himself as a leader in the team. People want to work for him and push for him," said Boullier.

Raikkonen's first visit to the Lotus factory in December for a tour of the facility and to attend the team's Christmas party generated a palpable sense of excitement among the team's employees.

"You can feel it when he is walking around the factory. Even before the announcement, people in the team were stopping me and asking about Kimi. His reputation preceded him in the factory. When he met with them [the team] at the Christmas party, he was friendly enough to spend time with people. Knowing that we have this guy, a world champion, with us is a big boost for the team and the motivation. You can see it in the way people react," said Boullier.

Although Boullier has already confirmed that the Finn's contract does not state that he is Lotus' number one driver, Raikkonen is beginning to establish himself as the team's de facto number one. Both Raikkonen and his team mate Romain Grosjean have been away from the Formula 1 grid for the past two seasons, but it was the 2007 world champion who was granted a private testing session in Valencia to re-acclimatise himself with a Formula 1 car and was chosen as the first person drive the Lotus E20 in Jerez after its launch, albeit only for filming purposes. Raikkonen was also assigned to do the first two days of official testing this week at Jerez.

Raikkonen began winning over the his team members as soon as he began working with them when he returned to the cockpit of a 2010-spec Renault R30 at Valencia's Ricardo Tormo circuit in Spain.

"Very few people in the team knew Kimi but after the first running he did in the car, they started to understand how he worked. The charisma of the guy is strong. He is a racer, he loves competition, loves Formula 1 and racing," added Boullier.

"You could feel that this is a guy who knows what he wants from the start. You get the respect and the credibility from the guys in the team if you deliver on the track. If you can give a clear indication of what you want, it pays off on both sides."

According to Autosport columnist Edd Straw, the general consensus in the paddock during the Jerez test is that Raikkonen has not lost any of his speed after two years away from Formula 1.

"Raikkonen is still quick. He was clearly leaning on the car from early on and was easily the most exciting driver to watch during the first day, showing that he was eager to get on with it, despite the main priority of his programme being data collection and validation," said Straw.

"That doesn't mean that the Lotus/Raikkonen combination is necessarily going to be winning races, merely that the Finn was on it immediately and looks like he means business."