CHICAGO -- The Cubs had to watch the Braves and Pirates secure postseason berths in back-to-back games, and Chicago manager Dale Sveum says he hopes the young players can learn from the experience.
"Any time you're losing, you're not going to enjoy it," Sveum said Tuesday. "I don't care who you are, it's not very fun. You hope you have people who get tired of [losing], and you appreciate winning and how things can turn around, like the Pirates and the Nationals. That's what you want to produce.
"Obviously, the Pirates have done a nice job in the last three, four, five years in the Draft, and some of the trades. It's not that far off [for the Cubs]. That's the message you try to send. It happens pretty much every year in every sport."
The Cubs now have lost 90-plus games for the third straight year, the first time they've done so since 1960-62.
"The only way you break [that trend] is winning," Sveum said. "The bottom line is getting off to a good start and believing you can win baseball games."
Starlin Castro and Anthony Rizzo have been the focus of attention for their struggles at the plate, but Sveum said their years aren't as bad as it may seem.
"The thing that gets blown out of proportion is that these are the two guys getting talked about all the time," Sveum said. "Are they having really bad, bad years? No. Rizzo has  doubles, he's got [77 RBIs], he's got home runs in the 20s, and Castro has been swinging the bat a lot better. These guys just have to keep playing and build on the adversity they've gone through this year."
The reason Castro and Rizzo are in the spotlight is primarily because both young players received long-term contracts, which Sveum acknowledged. Castro's drop -- he was batting .241, well off his two All-Star seasons -- is just a matter of maturity.
"It's easy to explain [a bad year] when you've been around the game long enough and see plenty of stars have a tough year," Sveum said. "It's just the nature of the beast."
• With top prospect Javier Baez not playing in the Arizona Fall League, the Cubs have added infielder Wes Darvill to the Mesa Solar Sox roster.
"He's an interesting player and does a lot of things well on the field and has good instincts," said Theo Epstein, Cubs president of baseball operations. "It'll be a nice opportunity for him."
Darvill, 22, a fifth-round pick in 2009, began this season at Class A Kane County, and batted .347 in 15 games before he was promoted to Class A Advanced Daytona, where he hit .253 in 79 games. A left-handed hitter, he played primarily at second base, but also played third and shortstop.
Albert Almora, the Cubs' No. 1 pick in the 2012 First-Year Player Draft and ranked by MLB.com as the organization's No. 2 prospect, was on the Mesa taxi squad, but now will have the chance to play every day, Epstein said.
The Cubs also pulled Arodys Vizcaino off the AFL roster so he could pitch in instructional league and are expected to add a pitcher to Mesa.
• Second baseman Darwin Barney did not start Tuesday but will be back in the lineup on Wednesday in the home finale. Barney was batting .156 in 20 games this month. Could he be worn down?
"You never know," Sveum said. "I don't know about physically, but mentally he's probably not where he wants to be."
• The Cubs have four players converting to catcher during instructional league, including Ben Carhart, Gioskar Amaya, Giuseppe Papaccio, and Jordan Hankins. Epstein said the moves were an "experiment" for the quartet.
Carhart played first and third with Daytona this season, batting .247, while Amaya played second base for Kane County. Hankins and Papaccio, both infielders, were selected in this year's Draft in the 11th and 18th rounds, respectively.
Carrie Muskat is a reporter for MLB.com. She writes a blog, Muskat Ramblings, and you can follow her on Twitter @CarrieMuskat. This story was not subject to the approval of Major League Baseball or its clubs.