WOKING, England (Reuters) - Lewis Hamilton's departure from McLaren has left Jenson Button with a more talkative and smiley team mate in Mexican Sergio Perez.
The 2009 world champion, who rubbed along with fellow Briton Hamilton without them being the greatest of mates, commented on the difference at the launch of the Formula One team's new car on Thursday.
"Checo (Sergio) has been around a lot this week, the last two weeks, which has been good," the 33-year-old told Reuters after pulling the covers off the MP4-28 alongside a team mate 10 years younger.
"It's good to see he has really been getting into the spirit of McLaren and spending a lot of time here, either doing sponsor activities or developing his relationship with the team.
"When Lewis and myself were here together we never used to see each other. It used to be one day in the simulator and out the other," he added.
McLaren were at pains during the Hamilton-Button years to present the pairing as two team players, drivers who genuinely got along despite being highly competitive rivals.
They certainly had a healthy respect for one another's talents and appeared together in commercials and as popular cartoon characters.
However, cracks began to show last season, particularly after 2008 champion Hamilton took to Twitter to complain - mistakenly - that Button had shown a lack of respect by apparently 'unfollowing' him on the social media site.
Socially, their paths rarely crossed.
With Hamilton now at Mercedes, Button finds himself in the role of McLaren's established driver with vastly more experience than newcomer Perez.
"We've spent a couple of weeks here and it's been very useful for him and for me to get to know each other but also for us to spend some time talking to the engineers and actually in the same room together discussing things," said Button of the new set-up.
"I don't know Checo that well but he is very excited, I can tell that. This is a massive challenge for him, as it is for all of us, to race for McLaren, and a great opportunity. It's good to see he is excited about the coming season."
Perez, with the smile of a man who has won the lottery and cannot quite believe his luck, felt he was getting on swimmingly.
"I think he's a great guy," he said of Button. "He has a lot of talent, he's a great champion, I admire him a lot and have a lot or respect for him. I am really looking forward to learning from him and working with him.
"I think together we are going to be good team mates."
Perez's confidence was evident, despite not having scored a point in the six races since his move to McLaren was announced last year, as he stood next to Button and declared the championship was his aim.
That is Button's aim too and this year, he agreed, was his best chance yet of adding a second title to his resume - not because of Hamilton's exit but because he simply had more experience of working with the team.
The Briton is now the most experienced driver in Formula One in terms of races after starting out with Williams in 2000 and team principal Martin Whitmarsh saw that as a big factor in a team with two 'number ones'.
"He's a team player and he's a winner," he said.
"People sometimes misinterpret Jenson, he's so laid-back and comfortable in his skin that you think 'has he got the hunger to do it?' But then you see what happens on the racetrack."
(Editing by Clare Fallon)