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As previously reported by Motorsport.com, Cassidy is unable to take part in this weekend's penultimate race of the season at Motegi following his visit to the Magione circuit in Italy to take part in a private Formula E test with Envision Virgin Racing last week.
Cassidy was always likely to have to skip the Fuji finale once it became clear it would clash with the official Formula E pre-season test at Valencia on November 28-December 1.
Yamashita, the reigning SUPER GT champion, will take over Cassidy's seat alongside Ryo Hirakawa, as the latter bids for a second title in the GT500 ranks individually.
Hirakawa trails championship leaders Sho Tsuboi and Kazuya Oshima by a single point.
Motegi will mark Yamashita's second start of the season following his one-off outing for fellow Toyota team SARD in the opening round of the season at Fuji, where Heikki Kovalainen was unable to race owing to travel restrictions.
His experience from that race, where he finished fifth alongside SARD regular Yuichi Nakayama, made him the logical candidate to stand in for Cassidy for the final races of 2020.
#37 KeePer TOM'S GR Supra
Photo by: Masahide Kamio
Once Cassidy signed his deal to race for Envision Virgin in Formula E in the summer, it seemed almost inevitable that one or other of his campaigns with TOM'S in Japan would be affected by the need to prepare himself for the 2021 season.
At first it seemed like Super Formula might be the casualty, as Formula E's pre-season test was originally slated for the first week of December. But when it was moved forward to the final weekend of November, suddenly it was SUPER GT that was in the firing line.
Cassidy's desire for a second SUPER GT crown to go with the one he and Hirakawa won back in 2017 isn't to be underestimated, so the decision to miss the final two races of the season is not one that would have been taken likely.
But the fact is that Cassidy missing SUPER GT but potentially still being able to complete the Super Formula campaign works out better for TOM'S than vice versa.
Yamashita has already proven himself a capable plug-and-play option in the Fuji season opener, and although the pressure is high he at least gets a race to re-acclimatise himself to the Toyota GR Supra this weekend at Motegi before the all-important title decider.
With such a capable substitute alongside him, Hirakawa can realistically aspire to be the first solo GT500 champion since Ryo Michigami in 2000, while TOM'S still has both of its cars firmly in the title hunt. If Cassidy can indeed see out the Super Formula schedule, then it's about as close to a win-win as could have been realistically hoped for.
Nick Cassidy, TOM’S
Photo by: Masahide Kamio
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