CHICAGO -- Unless the Cubs go on an unprecedented late-season tear, Sunday will likely mark the final matchup between long-time managers Lou Piniella of the Cubs and Bobby Cox of the Braves.

Before Saturday's game, Cox suggested, jokingly, that the Braves' success this season could lure him back for another campaign and that he would like to see Piniella hang around as well.

"[Bobby has] had a great, great career," Piniella said. "You can't have a much better career than Bobby Cox has had. He's had a really good season this year, and that's why he's probably thinking [about not retiring]. If he was having a year like we're having, he might not be [wavering]."

As for Piniella, he's solid in his desire to hang 'em up at the end of the season.

"I need to be home," Piniella said. "My circumstances changed a heck of a lot this year. I just need to be home. I'm concerned about my mom. I love baseball, but I love my family, and when you talk about your family, it's a lot more important than baseball.

"I appreciate that Bobby thinks I [shouldn't retire], but I'm going to be home. I'm going to enjoy my family, and that's the end of it. There shouldn't be any more discussion about this, because that's the way I feel."

There is a lot of recent baseball history tied up in the collective careers of the two skippers. The pair have combined to helm more than 8,000 games during 52 big league seasons, while accounting for 21 division titles, six pennants and two World Series championships.

Piniella, for one, thinks Cox is a no-brainer to eventually be enshrined in Cooperstown as a Hall of Fame manager.

"There isn't an iota of a doubt," Piniella said. "He's been an icon."

Not surprisingly, given his extended string of success with the Braves, Cox has gotten the better of Piniella over the years. Entering Saturday's game, Cox held a 37-26 advantage head-to-head against his Cubs counterpart. The pair first hooked up on Sept. 3, 1990, at Atlanta-Fulton County Stadium. That season, Cox replaced Russ Nixon as the Braves' manager after a slow start, while Piniella was in the midst of leading the Cincinnati Reds to a World Series title. Cox won that first meeting, 8-6.

Looking back, the two have opposed each other relatively few times. Piniella was still playing during Cox's first nine seasons as a big league skipper, and they've managed in the same league in just seven different seasons. They've never faced each other in the postseason.

Will there be managers who achieve the longevity of some of baseball's active veteran skippers, like Piniella, Cox, St. Louis' Tony La Russa and the Dodgers' Joe Torre?

"I don't know," Piniella said, "but the jobs, I think, have gotten a little tougher."

Colvin gets break to play in outfield

CHICAGO -- Tyler Colvin continues to prepare in earnest for his coming debut as a big league first baseman. But he got a break from his speed course on infield play Saturday, when Cubs manager Lou Piniella inserted the hard-hitting rookie in the starting lineup in left field. Piniella gave Alfonso Soriano the day off.

Colvin said the process of learning the new position is going fine, though there is only so much he can do in practice.

"It's a lot different when you get into a live game," Colvin said. "When you get a ball hit by Adam Dunn or someone, it's a little bit different.

"[The biggest challenge] is to be relaxed and make the plays I should make and not get too excited when I don't make the extraordinary play. It's just going over there and knowing what I'm supposed to do on certain plays."

The increased versatility could pay dividends for Colvin in terms of more playing time next season. All three of the Cubs' regular outfielders (Soriano, Marlon Byrd and Kosuke Fukudome) are under contract for next season. Adding the first baseman's glove to his arsenal could land Colvin significant playing time at four positions.

"It's an opportunity to play more often, and I can't be upset with that at all," Colvin said.

Of course, it's not like Colvin has rotted on the bench this season. Saturday was the 112th game he has played, third most on the Cubs. He's tied for second on the team with 18 homers. Colvin has shown tremendous pop when he makes contact but, as Piniella has suggested, his command of the strike zone is a work in progress.

"I feel like I'm coming along," Colvin said. "It's learning these pitchers and what they're trying to do to you. It's also not missing my pitches when I get them."

The Cubs expect Colvin to make his big league debut at first base during next week's trip to Washington.

Silva to throw simulated game Sunday

CHICAGO -- Carlos Silva is scheduled to throw a simulated game Sunday, the next step in his recovery from surgery for an irregular heartbeat. His next assignment will depend upon the success of that session, but it's believed that if all goes well, he'll make a couple of rehab starts in the Minors.

"We're going to get some hitters in there [against him], and we'll go from there," said Cubs manager Lou Piniella.

Silva is 10-5 with a 3.92 ERA for the Cubs in 20 starts this season. After a fast start, he has gone 9-7 with a 4.61 ERA since May 1.

Castro almost qualified for batting-title race

CHICAGO -- Cubs rookie Starlin Castro continues his slow creep toward qualifying for the National League batting title.

Entering Saturday's game, Castro had 369 plate appearances on the season. Players must average 3.1 plate appearances for each game a team has played to qualify, which works out to 502 for a full season. The Cubs' 123 games through Friday put Castro at 13 trips shy of the 382 plate appearances he needs to qualify.

Castro has averaged 4.5 plate appearances per game since he became the Cubs' primary No. 2 hitter in the lineup. So if he doesn't get any more days off, Castro should qualify by the end of August.

Unfortunately, Castro is losing ground in a batting race he has yet to officially enter. A 5-of-28 stretch over his last eight games has dropped Castro's average to .309, down from .320 on Aug. 12. As of Friday, Castro's average would rank sixth in the National League, 11 points behind circuit leader Joey Votto of Cincinnati.

Worth noting

The Cubs' record of 4-18 since July 27 is the worst in baseball. ... Outfielder Alfonso Soriano entered Saturday's game with 699 extra-base hits in his career, one shy of becoming the 173rd big leaguer to reach the 700 mark. ... Long-time Notre Dame men's basketball coach and ESPN hoops commentator Digger Phelps was set to sing during Saturday's seventh-inning stretch. ... Catcher Geovany Soto is expected to be activated from the disabled list Saturday. Soto has been out with a strained right shoulder.