driving the No. 52 for Dale Coyne Racing with Rick Ware Racing. Ryan Norman piloted the No. 52 at Mid-Ohio. Santino Ferrucci drove for Rahal Letterman Lanigan Racing in the Indianapolis 500. Ferrucci previously drove for Dale Coyne Racing from 2018 to 2020. Ferrucci was later signed for two additional races for the Detroit doubleheader. Ferrucci made further appearances at Mid-Ohio and Nashville. J. R. Hildebrand signed to drive for A. J. Foyt Enterprises for the Indianapolis 500 running a tribute livery for the 60th anniversary of A. J. Foyt's first win in the race. Stefan Wilson signed to drive for Andretti Autosport for the Indianapolis 500. It was Wilson's first IndyCar start since the 2018 Indianapolis 500. Oliver Askew joined Ed Carpenter Racing at Road America as a substitute after Rinus VeeKay suffered injuries in a cycling accident. Askew drove the No. 45 Rahal Letterman Lanigan Racing entry for the final three races of the 2021 season. Formula 2 and Alpine Academy driver Christian Lundgaard made his IndyCar Series debut at the Big Machine Spiked Coolers Grand Prix at Indianapolis Motor Speedway, driving the No. 45 Rahal Letterman Lanigan Racing entry. Alfa Romeo reserve driver and Scuderia Ferrari test driver Callum Ilott contested the final three races of the season, driving the No. 77 entry for Juncos Hollinger Racing. Team changes On October 28, 2020, it was announced that DragonSpeed, who competed on a part-time basis in the previous 2 seasons, left the IndyCar Series. Team Penske ended their partnership with Supercars team Dick Johnson Racing (with whom McLaughlin won his three titles) to make room for another IndyCar entry and thus returned to competing with four cars for the first time since 2017. Meyer Shank Racing added a second, part time entry for Hélio Castroneves after purchasing the car put up for sale by DragonSpeed. Chip Ganassi Racing also returned to a regular four-car team for the first time since 2017. Dale Coyne Racing announced a partnership with Rick Ware Racing (who field full- and part-time entries in numerous other series including the NASCAR Cup and Asian Le Mans Series) for the full season, changing the number of the team's second entry from No. 19 to No. 51. On February 18, 2021, Andretti Autosport mentioned that James Hinchcliffe's No. 29 entry would compete under the banner of "Andretti Steinbrenner Autosport", with one of the partners from the former