By Bruce Levine–

(670 The Score) — With a stalled free-agent market, there’s a question worth pondering.

Are the Cubs as currently constructed good enough to win the NL Central again and compete at the highest level for another World Series title?

The angst at the center of that question regards the pitching staff. As Jake Arrieta, a former rock of the Cubs rotation, remains a free agent, Chicago hasn’t made a splashy addition to its staff yet. The Cubs continue to have interest in Yu Darvish, the top available pitcher in free agency. Alex Cobb and Lance Lynn remain available as well.

The Cubs believe they’ve already done a lot of their heavy lifting with the addition of right-hander Tyler Chatwood and relievers Brandon Morrow and Steve Cishek back in December. By adding in free agency there, the Cubs didn’t have to deplete any of their position player depth in a trade. The Cubs also signed left-hander Drew Smyly, who’s recovering from Tommy John surgery and could be added to the bullpen late in the year if his rehab goes well.

As of now, the competition for the No. 5 spot in the Cubs rotation figures to be between Mike Montgomery, Jen-Ho Tseng and Alec Mills in spring training. Montgomery is the favorite to land that job. Of course, if the Cubs add another starter, Montgomery can serve as a swingman.

One silver lining for the Cubs’ rotation is that it shouldn’t enter spring training as worn out as in seasons past. Cubs starters didn’t go as deep into games in 2017, which contributed to a heavy bullpen burden. Chicago didn’t have a pitcher reach the 200-inning threshold last season. Jose Quintana threw 188 2/3 innings in time split between the White Sox and Cubs, Jon Lester logged 180 2/3 innings, Chatwood tossed 147 2/3 innings and Kyle Hendricks threw 139 2/3 innings.

The Cubs closely watched the pitch count of their starters in the first half of 2017 and had more success in stretching the rotation out after the All-Star break.

But four Cubs rotation members spent time on the disabled list in 2017, which is a big reason why executives Theo Epstein and Jed Hoyer want to add another starter this offseason. They know injuries are always one pitch away and want Montgomery to serve as the needed depth.

If the Cubs rotation can hold up, they should compete for a championship as constructed. After all, their position player group remains one of the best in the game.

In 2017, Willson Contreras had a breakout season, while Anthony Rizzo produced another superb year and Kris Bryant was solid despite battling some nagging hand and wrist injuries. Javier Baez also showed progress, and Ian Happ had 24 homers as a rookie.

Still, despite having the second-highest scoring offense in the National League, the Cubs’ front offense felt like the offense stagnated too often. Addison Russell, Ben Zobrist and Kyle Schwarber all struggled for long stretches.

The Brewers and Cardinals have improved their clubs this offseason, but the Cubs still remain the favorites in the NL Central as we wait for the high-profile free agents to make decisions.

“We are still working on some things,” Epstein said recently. “We aren’t done, but we have confidence in this group if it is the 25 we end up taking into spring training. Realistically, we would like to add another pitcher. We would like to bolster the depth of the staff.”

Bruce Levine covers the Cubs and White Sox for 670 The Score and CBSChicago.com. Follow him on Twitter @MLBBruceLevine.

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