MIAMI -- Nomar Garciaparra is continuing to make progress, and the shortstop could be back with the Chicago Cubs by Aug. 1.

Garciaparra is rehabbing in Mesa, Ariz., at the Cubs facility from a ruptured groin injured on April 20.

"He's in Mesa right now, and I was looking at the report and he was doing some first-to-third drills, running from first to third, and ground balls and things like that," Cubs athletic trainer Mark O'Neal said. "We're progressing, hopefully soon to some games in Mesa, but we're probably a week away from that.

"He's hitting and it just depends on how much time he'll need in the Minor Leagues to get ready," O'Neal said. "We're hoping by the third week in July he's in games in the Minor Leagues somewhere and that would give him 10 days to two weeks to be back here by the first of August. Position players are a little more predictable. With him, it's when he feels comfortable at the plate and can play a full game."

The Cubs had tentatively set an Aug. 1 deadline for his return after Garciaparra was examined in Chicago in June when he showed up for the Cubs-Red Sox series.

"We've been able to meet every goal," O'Neal said. "We just have to keep progressing with the intensity."

Pitch by pitch: Mark Prior will open the second half of the season on Thursday, starting against the Pittsburgh Pirates in the makeup game. The April 22 game was rained out, and rescheduled for Thursday at Wrigley Field.

Prior will be followed by Kerry Wood on Friday, then Greg Maddux on Saturday and Carlos Zambrano on Sunday.

Wood has a lot to look forward to in the second half after Saturday's game, in which he gave up two runs on six hits and one walk over 7 2/3 innings while striking out four. The strikeouts may be down, but Wood was able to keep his pitch count down.

"I feel like I've made progress every time out and I feel I've made better pitches every time out," said Wood, who won for the first time since April 24. He had missed two months because of a strained right shoulder.

"The results haven't quite been there yet, but I've been throwing for the most part the way I want to throw the ball, which is going after hitters and attacking the strike zone," he said. "The first pitch of the game was an out -- I had a couple innings where I had pretty quick innings. The opportunity for getting quick outs is better when you throw strikes."

First-half highlights: All-Star Derrek Lee entered Sunday's game leading the National League in hitting with a .375 average and is second in home runs and third in RBIs (68). With his home run on Saturday, he passed Sammy Sosa for the most total bases by a Cubs player in the first half. Sosa totaled 222 in 1998; Lee now has 225.

Lee also notched his 54th extra-base hit to pass Sosa, who totaled 53 in the first half of 2001.

Good student: This has been quite a first half for reliever Michael Wuertz, who has stayed with the big-league club the entire time. The main thing he's learned is how much mental preparation is involved.

"Being here for an extended amount of time has definitely been a learning process and not only physically, but mentally," Wuertz said. "[Mike Remlinger] and I talked about it [Friday] after the game. Both of us have to go out there and take one pitch at a time and let things fall into place from there. Having guys like him and [Ryan Dempster] and Glendon [Rusch] in the bullpen is a big help, too. We're going to rely on those guys.

"The best part is I feel great physically," Wuertz said. "Now it's time to take that next step forward."

Minor matters: Sean Marshall gave up one run on two hits over eight innings and struck out eight in Double-A West Tenn's 4-3, 10-inning win over Carolina on Saturday. David Aardsma picked up the win, pitching one inning in relief. ... Grant Johnson gave up seven runs -- one earned -- on six hits over 4 2/3 innings while striking out three in Class A Peoria's 10-5 loss to Wisconsin. Ryan Harvey was 1-for-5 with a double and two RBIs. ... No. 1 draft pick Mark Pawelek threw three scoreless innings, giving up two hits and walking one, in the Mesa Cubs' 7-3 win over the Athletics. Pawelek struck out two.

On deck: Lee and Aramis Ramirez will represent the Cubs in Tuesday's All-Star Game in Detroit. The rest of the team will be off until Thursday when they return to action against the Pirates at Wrigley Field for a four-game series.

Carrie Muskat is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.