Tony Kanaan made his first appearance with Ganassi in testing at Sebring on Wednesday, while Alex Tagliani reprised his stand-in role in the #10 car formerly occupied by Dario Franchitti.
Indianapolis 500 winner Kanaan, who announced in October that he would move to Ganassi from KV for 2014, was also joined on the track by the team's regular drivers Scott Dixon and Charlie Kimball.
Kanaan said that his main priority for the day was simply to settle in.
"It's my first day on the job, so it's still a little weird," he said. "It's a team that has been together for a long time and they've been very successful, so I'm actually trying to listen more than I'm talking. If I can bring something extra to improve what they already have, great."
Tagliani had covered for Franchitti at the season-finale at Fontana when the Scot was sidelined by injuries sustained in a crash in Houston.
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Those injuries led to his enforced retirement last month, but despite Tagliani's presence on Monday, the team is still yet to announce a replacement for the three-time Indy 500 winner and four-time series champion.
GANASSI'S CHEVROLET DEBUT
In addition to marking Kanaan's first outing with the team, the test was Ganassi's first opportunity to work with Chevrolet following its decision to part with previous engine supplier Honda.
Kanaan has previous experience with Chevrolet through his years with KV, which Ganassi managing director Mike Hull said offered a useful early benchmark.
"In a way, it's a good thing that Tony's already driven a Chevrolet car because he doesn't need to concentrate on the differences between that and a Honda product," said Hull.
"He can just concentrate on what we do as a team with the chassis. But with Tony we also have a fresh perspective on where Chip Ganassi stands in terms of how it creates an on-track product by comparison to where he's been in the past.
"So it's a big day for all of us here in terms of understanding how to make our product better."