CHICAGO -- The first domino of the Chicago Cubs’ offseason has fallen, as the team won’t exercise its 2018 option on pitching coach Chris Bosio after he's been on the job six years, according to a source familiar with the situation. The Cubs have not commented on the move, but team president Theo Epstein made one thing clear about his pitching staff this past season.

“The biggest factor is just the walks,” Epstein said in a Friday afternoon news conference. “We were 30th out of 30 in unintentional walk rate. The only team over 10 percent [walk rate]. That’s not acceptable. None of us feel good about that.”

The struggle with command carried over to the postseason, when the Cubs walked a whopping 53 batters in 10 games. But let’s be clear: It’s highly doubtful that one statistic alone has the Cubs moving on from Bosio. When it comes to coaches, so much of what they do goes on behind the scenes and involves one-on-one work with pitchers. When the work leads to a World Series title, you don’t question it. When a team falls short, everything can be scrutinized. Epstein forecast the departure in discussing what went wrong with his pitchers.

“Partly a player personnel thing,” he said. “It goes beyond that because if you look at it, and we have, virtually every reliever that we had walked more guys this year on a rate basis then they did on average through their career. It was common.”

Bosio is also a tell-it-like-it-is guy -- to both his bosses and his players. That can be a good trait, but perhaps the team believes another voice is needed to lead some younger pitchers who -- at least on the surface -- were advancing at a slower pace. And of course, that walk rate could not have helped Bosio’s cause.

One side note: Differing statements were made in recent days by Epstein and manager Joe Maddon regarding the coaching staff. Before NLCS Game 4 against the Los Angeles Dodgers, Maddon was asked if he wanted his coaching staff to return.

“Yeah, of course,” he responded. “Yes. Of course. Listen, the staff has done a great job. Our staff has been awesome. And they’re tight. It’s a tightly knit group. There is a lot of synergy involved. Nobody knows everything. Nobody is on their own little island. I like that. I really like that.”

A few days later, Epstein was essentially asked the same question.

“I don’t want to comment on the makeup of the coaching staff until I know what it is, exactly,” Epstein said before Bosio's option wasn't picked up. “Rest assured, Joe will have every coach back that he wants back. On the whole, it’s a great group.”

So who exactly dismissed Bosio?

Going forward, the more important question is whom the Cubs will hire to take Bosio’s place. Maddon is still tight with former Rays pitching coach Jim Hickey, who was let go by Tampa Bay at the end of the season.

“It surprised me,” Maddon said of the Hickey firing. “It surprised a lot of us.”

Maddon said the two “talk all the time,” usually when Hickey was driving to work over the causeway from Tampa Bay to St. Petersburg.

“He knows how much I love looking for dolphins driving over the Gandy Bridge,” Maddon said. “He’ll say, ‘I saw a couple dolphins this morning.’”

At the time, Maddon dismissed any notion of being reunited with Hickey.

“That’s not something we have discussed,” Maddon said.

Perhaps things have changed now that the Cubs' position is open. Another obvious candidate could be former Boston Red Sox manager John Farrell, a former pitching coach with the Red Sox -- if he wants to be a pitching coach again. Never dismiss the Boston ties when assessing a Cubs hire. Finally, a league source has already indicated that veteran pitching coach Mike Maddux would have interest, as he was let go as part of the Nationals’ decision to not renew the contracts of manager Dusty Baker or any of his coaches in Washington.

The offense

Another major discussion point during an hourlong news conference with Epstein on Friday revolved around the Cubs’ offense and, specifically, how good it was during the regular season compared with how bad it was in the postseason. There is no easy answer.

“It’s an interesting debate,” Epstein said. “We’re spending a ton of time talking about it behind the scenes. We have over the last three years. Asked all our players about it and the coaches. Our analytics guys are looking at it.”

It’s pretty simple. The Cubs scored the second-most runs in the National League, behind the Colorado Rockies, but averaged just 2.5 runs per game in the 2017 postseason. Epstein noted that the Cubs have had mediocre offense the past three postseasons.

“Is it the fact that our offense is depressed in October, or is it a small sample or a coincidence?” Epstein said. “Or is there something intrinsic in our personnel and our approach? How we do it? How we get to those runs we created in the regular season that makes us more vulnerable to the type of pitching and the type of preparation and advance scouting you see in the postseason? It’s virtually impossible to answer except to say you’re safer assuming there is some element that you can control.”

Incidentally, that statement could apply to the Cubs’ pitching woes as well, hence Bosio's being shown the door. The coaching staff is something the team can control.

Does that mean the same fate will land at hitting coach John Mallee’s doorstep? It’s not likely, as scoring the most runs in the NL over 162 games -- besides the team that plays at Coors Field -- has to mean something, right? Combined with the notion that the Cubs just don’t know what the answer is, the best idea is to tell Mallee and his hitters to focus on grinding out more at-bats, as they have done at times over the years and as the Dodgers just did to them.

“Most teams don’t hit [in October],” Epstein said. “You can’t count on being super-productive in the postseason on a consistent basis.”

The Cubs just want to be better than they are in order to give themselves a better chance in the playoffs. In other words, they want to get to the same run-scoring totals but perhaps in a different way. That can be addressed internally or through player acquisitions. Both are likely to happen.

The offseason

Those assuming a new leadoff hitter is a high priority for the Cubs this winter might be disappointed.

“In certain situations, depending on the rest of your roster, it can start to slide toward luxury -- not necessity,” Epstein said. “We’d rather have one, but I’m not going to sit here and say by Opening Day we’re going to have a designated leadoff hitter that’s going to be our guy and make things go.”

Make no mistake, the Cubs would love to have a player such as Dexter Fowler to rely on, but it’s not a priority. They could not have had a worse situation at the leadoff spot in 2017, and they still scored the second-most runs in the league. What the Cubs want to be able to do is grind out enough at-bats that it doesn’t really matter who leads off.

• Starting pitching is a high priority, considering Jake Arrieta and John Lackey are free agents.

“There’s potential for real work to be done in the starting rotation,” Epstein said.

The door isn’t closed on Arrieta returning, but the Cubs are likely to sign at least one pitcher from outside the organization. Rays pitcher Alex Cobb is a free agent and would be a good fit. He played for Maddon previously.

• Epstein said this could be the offseason when the team trades from the major league core, as the Cubs have used up most of their farm system in previous deals. It’s not for certain that one of their secondary guys would be moved, but it’s a greater possibility than it was in the past.