INDIANAPOLIS (AP) — A.J. Watson, a mechanic and designer who played a key role in several Indianapolis 500 victories in the 1950s and ’60s, died Monday at age 90.

Indianapolis Motor Speedway officials confirmed the death, citing members of Watson’s family. Speedway President Doug Boles called Watson one of the most innovative mechanics and car builders in the track’s 105-year history.

Watson designed and built roadsters in the 1960s — one of which A.J. Foyt drove to the second of his four Indy wins. Watson was the chief mechanic on four cars that reached Indy’s Victory Lane between 1955 and 1962, three of which he built. Watson also constructed three other Indy-winning cars in the ’60s.

Foyt said he had seen Watson last week and it was “hard to believe he’s gone.”

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