The Cubs will put Stewart on the disabled list Thursday. The club hasn't said who will take Stewart's spot on the roster, but it could be infielder Luis Valbuena, who was batting .303 in 58 games at Triple-A Iowa. He has played mostly second base for the Iowa Cubs.
"[Stewart] has been battling as much as he can through it," Cubs manager Dale Sveum said. "It got to the point today where it was pretty bad and we took him out of the lineup. We'll get it evaluated and put him on the DL [on Thursday]."
New Cubs hitting coach James Rowson spent extra time with Stewart at the cage during batting practice on Wednesday. The Cubs have been trying to get the third baseman on track. He was batting .201 overall, and .226 in his last 11 games.
"There's been plenty of things suggested," Sveum said before Wednesday's game. "It's just a matter of being able to apply it. He's got to be able to apply things in the game and in batting practice and the willingness to make adjustments. That's the bottom line, we've got to make adjustments."
Stewart's best season power-wise was 2009 when he hit 25 homers, 19 doubles and three triples. Last year, he was slowed by injuries, and so far this season, he had five homers, five doubles and two triples in 179 at-bats over 55 games.
"We've got to start getting some production," Sveum said.
Stewart has tried to play with his left wrist taped.
"I'm sure it bothers him but when you watch him take batting practice, it's not bothering him then because he's hitting 400 foot home runs all the time," Sveum said.
Rowson, 35, who was the Cubs' Minor League hitting coordinator, took over Tuesday, replacing Rudy Jaramillo, who was dismissed.