Who's Chicago Cubs' ace? It's a good argument to have

Jon Lester or Jake Arrieta in the one-game wild-card game?

Cubs manager Joe Maddon says he doesn't mind fans speculating about it even if he won't.

"They haven't asked me, but let's just win the division," Maddon said Friday at U.S. Cellular Field. "If you're a fan, you're supposed to do those things. I'm not supposed to; they are supposed to."

Of course, that kind of talk is getting too far ahead of things for a couple of reasons. First, the Cubs still have to hold on to their wild-card spot, something they're working quite well to do. Second, they may not have the luxury of choosing who would start the playoff game.

Lester was signed last winter to a six-year, $155 million contract to be the Cubs' ace. However, Arrieta has been the more effective of the two pitchers.

General manager Jed Hoyer wasn't biting, either.

"I saw Joe's answer, and I thought it was the right answer," he said. "Let's have a five-game series and forget about it. First of all, I think it's great we have two guys to have that discussion about. We've been really hot. We've put ourselves in a great position. There's a long way to go.

"This is a big series (against the White Sox). We're going to go out on the West Coast and have big series. We're going to play six or seven games against the Cardinals and Pirates the rest of the way. We have a long way to go, so to even talk about that kind of stuff is so incredibly premature.

"We have to keep grinding out game after game."

Quiet on trade front:

Jed Hoyer said nothing was imminent on the trade front as teams monitor the waiver wire. The Cubs may want to add a player, but they also like the chemistry on the current roster. They've been linked in trade rumors with Phillies second baseman Chase Utley.

"You're always very aware of the team dynamic," Hoyer said. "It's a fragile thing. The team has been together a long time. At the same time, you can't shy away from bringing in a player who could make you better. It's a balancing act and one that you talk through and treat with a lot of care. There may never be a right or wrong answer."

Feeling for Farrell:

Jon Lester expressed his support for Boston Red Sox manager John Farrell, who announced he has what he termed a "highly curable" form of lymphoma. While with the Red Sox early in his career, Lester beat lymphoma and has been active in raising funds for cancer research.

"Obviously, we go pretty far back," Lester said. "I talked to him a little bit already, so that was good. He seems pretty positive."

Rosscup optioned:

The Cubs activated left-handed reliever Zac Rosscup off the disabled list and optioned him to Class AAA Iowa.

Right-handed reliever Rafael Soriano may be getting close to going out on a minor-league rehab assignment, but he may not be activated until it's time for September call-ups. Soriano is on the DL with right-shoulder inflammation.

"He's doing well," Joe Maddon said. "He's progressing well. I can tell when I talk to the guy - he smiles easily now."