Since July 10, Castro is batting .432 with 13 runs, 11 doubles, two triples, a home run, 10 RBIs and 13 multi-hit games. Part of the surge during that stretch could be because his family has been with him, joining him in Chicago from the Dominican Republic since the All-Star break.
"The kid's a good player," Cubs manager Lou Piniella said of Castro. "He's getting confident with that bat. He's hitting the ball in the gaps and this kid's going to be a good player for a long time in the big leagues."
Posey, named NL Player of the Month for July, was batting .355 with a .540 slugging percentage. Davis has 53 RBIs. Atlanta's Jason Heyward, the preseason favorite for the NL rookie award, has 50 RBIs and 11 homers in 90 games. Mike Stanton drove in 52 runs in 53 games at Double-A before he was called up to the Marlins in early June. He's driven in 31 in 47 games so far.
Colvin has played in the most games (99) and leads all NL rookies with 17 home runs. He's got two months to catch Billy Williams' Cubs record for homers by a first-year player (25) set in 1961. Colvin's homers are the most by a Cubs rookie since Geovany Soto hit 23 in 2008.
Soto won the NL Rookie of the Year Award that season. He's impressed by the Cubs' 20-year-old shortstop, who has overcome a .227 June.
"He's impressive," Soto said of the slender infielder. "I think he's the real deal. He makes adjustments at home plate. He's so young. At his age I was in [Class A] ball. It's good to see him and Colvin, too."
It's taken some time for Castro to get used to the big leagues. He has never played at the Triple-A level, making the jump from Double-A Tennessee to the big league team on May 7. What's been the difference since getting the call?
"Getting used to the game, it's a little faster here than Double-A," Castro said. "It took me some time to get used to that."
He isn't perfect and has kept Cubs infield coaches Alan Trammell and Ivan DeJesus busy.
"He makes his mistakes and you talk to him and you live with it, but he's learning on the job," Piniella said.
"When you have talent and you're smart, talent takes over," Cubs third baseman Aramis Ramirez said. "[Castro] doesn't make many mistakes and he has all the talent in the world. He can run, he can hit, he can play defense. When you're smart and put all those things together, you're going to be successful."
In his debut game May 7 in Cincinnati, Castro hit a home run in his first at-bat and added a triple and drove in six runs. Asked to compare those early May games to now, Castro smiled.
"Cincinnati was different because I had goosebumps," he said. "Right now, I feel confident."
It shows in his play on the field and at the plate.
"He's going to be a special player," said Cubs second baseman Blake DeWitt. "He's really coming into his own."