MIAMI -- As the Nationals near the midway point of their season, they also appear closer to full strength.

Ryan Zimmerman went 0-for-4 and played nine innings at first base for Double-A Harrisburg on Wednesday in his fifth rehab game, appearing in three straight contests. Washington expects Zimmerman to join the club this weekend in Detroit against the Tigers, barring any setbacks.

"He felt good," Nationals manager Dave Martinez said. "He made some good defensive plays. We're going to see how he rebounds [Wednesday] and go from there. But he says he's progressing well. He said the baseball soreness is getting out of him now. He's getting used to playing again, so that’s good news."

Zimmerman has been on the injured list since April 28 with plantar fasciitis of his right foot. He appeared in just 22 games before then, compiling a .213/.302/.373 slash line with three doubles, three home runs and 11 RBIs.

In Zimmerman's absence, the right-handed-hitting Howie Kendrick, as well as left-handed-hitting Matt Adams and Gerardo Parra, have gotten reps at first base. The Nationals will need to figure out how to divvy up playing time upon Zimmerman's return.

"We haven't decided what kind of moves we’re going to make," Martinez said. "With him, we have to be really careful. I've talked to him a lot. He's not going to come here and play every day, nine innings, and he understands that Howie and Matt are both doing well, so they’re going to get some playing time as well.

"For me, it's a good problem to have because regardless of if he starts or not, you have two guys on the bench that can really do some damage somewhere along the way. So that's a good problem to have for me. But we'll figure all that stuff out when he's ready and gets here. And again, we'll see how he's doing on a daily basis."

Relievers progressing
On the relief front, both Kyle Barraclough (right radial nerve irritation) and Justin Miller (right rotator cuff strain) completed a side session on Wednesday as part of their throwing program. They will head to West Palm Beach, Fla., when the Nationals leave South Florida following Thursday night's series finale to continue rehabbing.

Barraclough has been sidelined since June 16, while Miller went on the injured list on May 18 and sustained a setback after just one outing with Harrisburg on June 8. Washington called up veterans Fernando Rodney and Jonny Venters, a couple of midseason pickups, on Tuesday to shore up the bullpen.

The hope is to get Barraclough and Miller on assignments soon, though the length of their stints could vary.

"We want to build them back," Martinez said. "[They'll] probably start off pitching once every two days, then get in every other day, then get in back-to-back days and see how he feels."

Nationals sign Cronin
The Nats signed fourth-round Draft pick Matt Cronin for $464,500 (full pick value), according to MLB.com's Jim Callis. The University of Arkansas left-handed reliever has high spin on his 92-96 mph fastball and curveball.