Frazier hit an RBI single in the first inning off Gonzalez Germen, who was pulled after getting only two outs. Frazier also made two errors at third base.
Brennan Boesch, making a bid to win a spot as the Reds' fourth outfielder, also hit his fourth homer and doubled.
Reds closer Aroldis Chapman started and struck out the side in his only inning. Manny Parra and Tony Cingrani had scoreless outings as Cincinnati used eight pitchers.
Cubs second baseman Javier Baez had two hits and made two errors. Dexter Fowler hit his first home run of the spring.
Germen gave up four hits and walked three.
Copyright 2015 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.