In mid 2018, it was announced that Mir would end his contract with Marc VDS two years prematurely, in order to move up to the premier class with the Suzuki factory team on a two-year deal to replace the outgoing Andrea Iannone. In his rookie season in 2019, he achieved consistent top-10 finishes but missed two rounds due to a pulmonary contusion suffered in a crash in testing at Brno. He was replaced by Suzuki test rider Sylvain Guintoli. Mir achieved a season-best finish of 5th place in Australia. He finished the season with 92 points, 12th in the overall standings and second best rookie behind former Moto3 Leopard Racing teammate Fabio Quartararo.