CHICAGO -- Addison Russell's name has been listed above a closed locker inside the Cubs' clubhouse since the team's first homestand, but there remains no established date for the infielder's return. All that is known at the moment is that he still has work to do on and off the field with Triple-A Iowa.

One of Russell's tasks on the field is to become acclimated again with second base, which is a position he has not played with any regularity since 2015. Given Javier Báez's stellar play as Chicago's everyday shortstop, Russell is preparing for life on the other side of the bag. Third-base coach Brian Butterfield, who also serves as the team's infield instructor, is confident Russell can make a swift and smooth transition.

"You're playing from a different angle," Butterfield said prior to Friday's game against the Cardinals. "You can play second base more side to side, whereas shortstop you're playing up the funnel. You've got to attack and play toward home plate. Obviously, starting the double play, it's opposite footwork. Turning the double play, it's basically opposite footwork. It's just making that adjustment. As athletic as Javy and Addison are, I think they can make that adjustment fairly quickly."

The Cubs reinstated Russell from the restricted list on Thursday after he completed a 40-game suspension for violating MLB's Domestic Violence Policy, then optioned him to Iowa. Russell has played mostly shortstop in the Minors, but he started at second base on Monday and will continue to log innings at that position.

Cubs manager Joe Maddon said the goal is to get Russell enough innings and at-bats so that he not only feels ready, but the Cubs can also be confident that his return will not disrupt the defense or lineup.

"Guys right now, they're not in midseason form, but guys are pretty much advanced," Maddon said. "And we just want to make sure that he's ready to play here. Get your at-bats. Get your reps. Make sure you're not sore. How's the arm playing? Everything, the whole game. It's just about actually being fair to him, too, to make sure that he's ready to go by the time he's back up here.

"It's not far off. It's not far of from what I understand. Actually, I've heard some good things. Typically, everybody wants to rush things. When you don't have to rush things, it's actually a better method, I think."

The Cubs are also hesitant to move Báez off shortstop, where he was tied for the MLB lead with seven Defensive Runs Saved entering Friday. Butterfield said focusing on shortstop since the outset of Spring Training has helped Báez strengthen some defensive components, including being more aggressive toward balls in play.

"He's got such a great throwing arm," Butterfield said. "He really never got in the habit of creating momentum, because he didn't need to. Now, he's making that adjustment. ... He's got such great aptitude, and he's such a great athlete that things have a tendency to happen quickly. It may take a little while for little incremental things to take place at shortstop, but he's starting to get it."

De La Cruz reinstated
The Cubs reinstated right-hander Oscar De La Cruz from the restricted list on Friday, following the completion of an 80-game suspension for a violation of MLB's Joint Drug Prevention and Treatment Program. De La Cruz will report to Double-A Tennessee.

De La Cruz received the suspension in July 2018, when he was ranked third among the Cubs' Top 30 Prospects by MLB Pipeline. The 24-year-old is now ranked 22nd on that list. In three recent outings with Class A Advanced Myrtle Beach, De La Cruz posted a 2.47 ERA with 17 strikeouts and five walks in 15 innings.

To clear a spot on the 40-man roster, the Cubs returned righty Tony Barnette from his rehab assignment and transferred the reliever to the 60-day injured list. Barnette recently reported tightness in his right shoulder and will return to Mesa, Ariz., to continue his rehab work.

Worth noting
• Entering Friday, Ian Happ had nearly twice as many walks (11) as strikeouts (six) in his past 13 games for Iowa, posting a 11.3 percent strikeout rate in 53 plate appearances over that stretch. That comes after Happ had a 36.7 percent strikeout rate in the previous 14 games (22 punchouts vs. three walks in 60 plate appearances).

"I've been watching the videos," Maddon said. "I just see a shorter path to the ball from the left side. His right side is as good as I've seen it. I've known him for just a couple years, but the right side is a much more functional approach. The left side, more direct to the ball [lately]. That's the best way I can describe it."

• Kris Bryant was back at third base on Friday after spending Tuesday and Wednesday as the Cubs' designated hitter in Seattle due to a mild hamstring issue. Bryant has spent time in the outfield in nine of his past 14 games and will continue to get regular work as an outfielder, per Maddon.