Polanco could not play Monday because of stiffness in his lower back, which has bothered him for several days. The severity of the injury is unclear, although Polanco spent time on the disabled list last season with lower back inflammation and was scheduled to see team physician Michael Ciccotti. Polanco previously missed time this season because of an injured wrist and ankle, although he has not been on the DL.
Polanco is hitting .255 with two home runs, 19 RBIs and a .628 on-base-plus-slugging percentage. His OPS is 119 points below his career average.
Asked if Polanco can still be an everyday player, Manuel said, "The last couple years, it's been tough for him to stay on the field. Polly used to be a guy that was set on playing every day. I'm sure when he's hurting and he can't play, it bothers him."
Since going 2-for-4 on June 4 to push his batting average to a season-high .294, Polanco has hit .184 with eight RBIs and a .494 OPS.
"Every now and then when he does hit a ball hard it seems like somebody catches it," Manuel said. "It seems like he's always having to beat something out. He hasn't been getting a lot of hits. At times, he puts the fat part of the bat on the ball still."
Ty Wigginton started at third base Monday night, batting seventh.