DeShields has made several standout catches in center field, where he owns a .984 fielding percentage this season. His most recent defensive highlight came on Wednesday against the Padres, when DeShields robbed Hunter Renfroe of a home run on a leaping catch at the wall.
Banister said DeShields has had to make major strides in his defense over the past two years to even be considered an elite defensive outfielder, especially since he came up as a second baseman.
"That's the beauty of what we do," Banister said. "We ask guys to change positions. Nobody really sees the mistakes, the inabilities or the nuances. The speed of the game here exposes all the things that you have to work on. To make a change at this level is tough. This was still a young player."
Banister added that he's also seen DeShields take on more of a leadership role in center field this season.
"I love how he's playing," Banister said. "I love the maturity that he's shown. You gotta lock in on him and see how he's taking charge, moving guys in the outfield, talking to his corner outfielders as he's seeing things from center field -- just how he shows up for every pitch."
Perez begins rehab stint Catcher Carlos Perez went 2-for-5 with a double, a home run and three RBIs in a rehab appearance for Double-A Frisco on Thursday, his first action since landing on the disabled list with a right ankle sprain on June 16. He caught nine innings in Frisco's 10-inning game.
Banister said Perez didn't have any setbacks and is progressing as expected.
Martin Perez scheduled for second rehab start Left-hander Martin Perez is scheduled to make a rehab start for Frisco on Saturday. On the disabled list with nerve inflammation in his right arm, he made his first rehab start on Monday for Class A Hickory.
Rangers beat • The Rangers entered Friday's series opener against the White Sox winners of their past four series. Texas has won three straight series openers.
• Entering Friday, Rangers hitters had been hit 22 times in the month of June, matching the club record for any month.
• Keone Kela is 20-for-20 in save opportunities this season, which is the longest season-opening save streak in club history. Kela's 22 straight saves dating back to last season is the longest active run in the Majors.
Wesley Dotson is a reporter for MLB.com based in Texas.