Renner, a shortstop, scored a run with four assists and two putouts in the victory. He was named MVP.
John Ermis (1-0) earned the win after coming in with two outs in the third inning and the bases loaded. Ermis escaped the jam and pitched into the seventh before being relieved by game one winner Brandon Berger, who retired the final two Coronado batters.
The title is the third for Brazoswood (34-8) and first since 1992. Coronado (33-16) matched its best finish previously (1995).
William Easter added three hits while Dalton Perry and James Cantu added two this for the Bucs.