Jim Harbaugh is sending off assistant coach Tim Drevno with words he could only muster.USC announced Monday night Drevno will become the offensive line coach there. He will be with the 49ers until their season ends. He worked as co-offensive line coach with Mike Solari in San Francisco. Drevno was with Harbaugh for the past 10 years at UC San Diego, Stanford and now the 49ers.In comments distributed by the team, Harbaugh had impassioned comments about his departing coach:"It is with great emotion, pride and excitement that we wish Tim Drevno continued success in his professional journey at The University of Southern California.