The Cubs, who went 2-4 on their six-game road trip against the Cardinals and Pirates, struggled offensively, batting a collective .169 in the six games, with three home runs and 10 RBIs.
"Right now, we have to get some production out of [Bryan] LaHair and [Luis] Valbuena, who looks like he's in a mini slump, too," Sveum said. "We have a lot of guys right now not on all cylinders. [Starlin] Castro is getting his hits here and there. [Alfonso Soriano] has been fine. [Geovany Soto] has had great at-bats and is swinging OK. We've got to get a little bit better production out of some spots."
Entering Friday, LaHair was batting .231 in 17 games in July, with one home run and three RBIs, while Valbuena was hitting .190 in 20 games this month.
Double-A Tennessee outfielder Jae-Hoon Ha suffered a concussion when he crashed into an outfield wall Thursday night against Jacksonville, and he will be sidelined seven to 14 days, the Cubs said.
Ha, who played for the World team in the All-Star Futures Game, was taken off the field on a stretcher, then taken by ambulance to a Jacksonville hospital. According to the Smokies Radio Network, Ha was responsive and talking before he left the field.
Blake Parker, on the disabled list since June 6 with a stress reaction in his right elbow, threw off the mound for the first time since he was injured. Parker threw 30 pitches on Friday. There's no timetable for his return.