CHICAGO (AP) – Mike Fiers tossed 7 1-3 solid innings to lead the Milwaukee Brewers to a 3-1 win over the Cubs on Wednesday, their eighth straight victory against Chicago.   Fiers (8-6) held the Cubs to four hits and struck out six, helping Milwaukee beat its division rival for the 13th time in 16 games this season. The Brewers have won eight of nine overall and moved within five games of .500 for the first time since July 21.   Fiers sent down 14 straight batters at one point and won his second straight start.  John Axford finished up for his 22nd save in 30 chances.   Jeff Samardzija (8-12) gave up seven hits and three runs – two earned – in seven innings for the Cubs. He struck out 10.        Jean Segura stroked a go-ahead single in the seventh for Milwaukee.