Ohio State star quarterback CJ Stroud paid tribute to Dwayne Haskins on the practice field on Monday ... penning a touching message to the late NFLer on his jersey.

OSU shared photos of the tribute during the Buckeyes' training sesh -- two days after Haskins was hit by a dump truck on a highway in Fort Lauderdale, Florida.

The Buckeyes QB -- who's entering his third season with the program -- inked "LLDH7" (Long Live Dwayne Haskins) and "RIH SIMBA" on his practice jersey ... showing respect for the former 15th overall pick in the 2019 NFL Draft.