NEW YORK -- Willson Contreras has been on the move constantly over the past week. The Cubs catcher has been bouncing between the field, weight room and training room, checking off a list of to-do items to keep strengthening and testing his right hamstring.

On Thursday, Contreras was on the move again. Following a round of regular batting practice and baserunning drills at Citi Field, the All-Star catcher was packed, dressed and headed out the door. He will begin a Minor League rehab assignment with Triple-A Iowa on Friday.

"Finally," Contreras said as he exited the visitors' clubhouse.

Contreras was in the midst of what was shaping up to be a career year when he strained his right hamstring during an Aug. 3 game against the Brewers. If everything goes according to plan, he might be able to return from the 10-day injured list in around a week's time, but there are still boxes to check in his comeback.

The first game-related step will be catching two or three innings and having a couple of at-bats on Friday with Iowa. Then Contreras will likely take Saturday off while the Cubs monitor his recovery from his first game action in nearly a month.

"I'm pretty confident in the leg based on what the [medical] guys have been saying," Cubs manager Joe Maddon said. "They really feel good about his strength level, and that's probably the most important thing. Then after that, it's just creating timing at the plate. He's eager, man.

"I know you guys have seen him. He just came in and said goodbye. So I don't anticipate too long, but you just have to listen to his leg, pretty much."

In 87 games this season, Contreras has hit .275 with 19 home runs, 57 RBIs and an .890 OPS. He was voted into the National League's starting lineup at the All-Star Game for the second consecutive year. While Contreras has been sidelined, the Cubs have used a combination of Victor Caratini and Jonathan Lucroy. Having two catchers of that caliber will also help ease the starter back into the mix when he does return.

"It's happening at a good time. He's had a little bit of a break," Maddon said. "He's a big part of our team, our offense, and what he does defensively to stop the other team is also invaluable. His energy, all that stuff's in play.

"So yeah, I'm just curious to see if he can get his timing back quickly. That'll be the big thing at the plate. I anticipate behind the plate -- receiving, throwing, etc. -- should be pretty normal stuff for him."

Rizzo watch

First baseman Anthony Rizzo remained out of the starting lineup against the Mets on Thursday, marking the fourth straight game he has missed due to a back issue. Maddon was not optimistic that Rizzo would be able to return for Friday's afternoon game at home against the Brewers, either.

"I would be surprised if he walks in and said he felt good enough to play," Maddon said prior to Thursday's game in New York. "I'm not anticipating that."

During pregame on Thursday, Rizzo was on the field going through a series of exercises. The first baseman also said Wednesday that he began swinging a bat lightly.

"He's getting better, but he's not ready," Maddon said. "It's just a day-to-day kind of a thing. He looked better walking around today, but I don't have any kind of specific day yet for you."

Lee Smith Day

The Cubs plan on honoring recent Hall of Fame inductee Lee Smith prior to Sunday's game against the Brewers at Wrigley Field.

Sunday will mark the 39th anniversary of Smith's debut, and the Hall of Fame closer went on to save a then-record 478 games over parts of 18 seasons in the big leagues. Smith notched 180 saves for the Cubs, and the team plans on raising a flag featuring his name and "180" at Wrigley as part of the celebration.

Smith will throw out the ceremonial first pitch, lead the seventh-inning stretch and his Hall of Fame plaque will be on display at the ballpark until the seventh for fans to view.