You've heard plenty about the Cubs' "core" players
At the minor-league level, the core included Javier Baez, Jorge Soler and Albert Almora to start the season. You can safely add this year's top draft choice, Kris Bryant.
At the major-league level, the core included Starlin Castro, Anthony Rizzo and Jeff Samardzija. By now, it's safe to say Travis Wood and Welington Castillo have earned their welcomes to the core.
We'll stick with the major-leaguers today. It's been an interesting season for most of these players, especially when it comes to first-half and second-half splits.
Castro, Rizzo and Castillo went a combined 2-for-11 Thursday night in a 3-1 loss to the Pirates at PNC Park.
There have been ups and downs, and whenever someone asks about players such as Rizzo and Castro, my answer is, "We'll know next year."
In other words, we'll see if the players make the necessary adjustments it takes to succeed at the major-league level after each made promising starts only to fall off in certain areas this season.
That said, let's take a look at some key first-and second-half splits for some core players.
•Rizzo: The first baseman looked frustrated in Wednesday's series finale at Cincinnati, where his batting average for the season dropped to .228.
The 24-year-old Rizzo has been a puzzle. He took 21 home runs and 73 RBI into Thursday. Before the all-star break, Rizzo had a line of .241/.328/.441 for an OPS of .769. He had 13 home runs, 54 RBI, 41 walks and 71 strikeouts.
After the break, Rizzo entered Thursday at .204/.317/.372 for an OPS of .689 with 8 homers, 19 RBI, 31 walks and 43 strikeouts.
Rizzo came up to the Cubs from the minor leagues last year in late June and put up a solid line of .285/.342/.463 for an OPS of .805. He had 15 homers and 48 RBI.
The bright side for Rizzo is that the power numbers still are there and his walk rate has gone from 7.3 percent to 11.6 this year.
This year's numbers suggest a Carlos Pena-type player with the low batting average and the home runs, but Pena has a lifetime .348 OBP. The Cubs are banking, quite literally considering the contract extension they gave Rizzo, on him being a franchise player. The next couple of seasons will be quite telling.
•Samardzija: Manager Dale Sveum said Samardzija no doubt is feeling the effects of his first full season as a major-league starter; the Cubs shut Samardzija down in early September last year.
Before the break Samardzija was 5-9 with a 4.06 ERA and a WHIP of 1.30. Since the break he's 3-3 with a 5.09 ERA and a WHIP of 1.46.
Few players work harder than Samardzija, who has made strides in several areas. Despite talk of Samardzija either getting or not getting a contract extension, there still is no rush on either side. It seems time here is on everybody's side.
•Castillo: The 26-year-old catcher has seen dramatic improvements in his offensive numbers from the first half of the season to the second, particularly with getting on base. In the first half, Castillo was at .266/.324/.353 for an OPS of .677.
After the break he has been at .291/.401/.453 for an OPS of .854. During the first half you could find Castillo's name (along with Castro's) at the bottom of the list in walk percentage.
He took just 1 walk in April, 4 in May and 5 in June. Then came July and August, when Castillo finally adopted a more patient approach at the plate and drew 10 bases on balls in each month.
Along with his defensive work behind the plate, he's establishing himself as one of the top catchers in the National League.