FORT WORTH, Texas (AP) -- Graham Rahal will keep driving for his father's IndyCar Series team.
Rahal, who was in the last year of his contract with Rahal Letterman Lanigan Racing, has signed a five-year extension through 2023.
''I know you're going to say I'm biased, but I admire and respect Graham's work ethic on and off the track for our team, for our sponsors,'' Bobby Rahal, the three-time open wheel champion and 1986 Indianapolis 500 winner, said Friday. ''We're really pleased that we now go forward for the next five years as a team together because I think the best five years of Graham's career are ahead of him.''
Before joining his father's team full-time for the 2013 season, Graham Rahal came up through the racing ranks with other teams. That had always been part of the plan, to give the younger Rahal the opportunity to make a name for himself.
This time, Graham Rahal said there was some ''testing the waters'' and talks to others before he re-signed with his dad's team.
''All that sort of stuff, that's natural. As you really look at it, you take a step back, RLL has done a tremendous job and has proven themselves, ourselves, to be one of the premier teams in the series consistently,'' the 29-year-old driver said. ''Probably the most consistent team over the last few years other than maybe Penske. I think from that perspective it was great.''
Graham Rahal has six IndyCar Series wins, five of them coming since joining the team in 2013. His best points finish was 2015 when he was fourth, before finishing fifth in 2016 and sixth last season. He is seventh through eight races this year, including a runner-up finish at St. Petersburg in the season opener.
At age 18 in 2007, he started in Champ Car with Newman Haas Lanigan Racing. He moved the next season with the team to the IndyCar Series, where he won his series debut at St. Petersburg, his only win until 2015. He also drove two seasons for Chip Ganassi on a team with perennial title contenders Dario Franchitti and Scott Dixon before joining his father's team full-time.
Contract negotiations for the new extension were handled by the 29-year-old driver's management team and Mike Lanigan, one of the other team co-owners along with former television talk show host David Letterman.
''That at least takes the two of us and the heart out of it, puts it more into business hands,'' Graham Rahal said. ''But I would say our relationship is really in many ways much more just father-son.''
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