With the Major League Baseball season less than a week away, fans and baseball experts are already trying to predict who will raise the World Series trophy in October. Two favorites are the Chicago Cubs, who won the crown last year, and the New York Mets, who went to the World Series two years ago and made a playoff appearance last year.

Both teams’ front offices have assembled exciting teams stacked with talent, though they took opposite approaches in assembling their squads. The Mets’ success comes from their plethora of young pitchers, the Cubs from their stockpile of hitting prospects. But while both rebuilding methods have proved fruitful in the past, the Cubs’ method seems more sustainable and less risky.

Since Sandy Alderson took over as general manager in 2010, the Mets’ front office has pursued and developed young power arms. Along with Matt Harvey and Jacob DeGrom — star pitching prospects who were already in the Mets’ farm system when Alderson arrived — the Mets have drafted and traded for All Star pitchers Zack Wheeler, Noah Syndergaard and Steven Matz. Harvey, 2015 National League Comeback Player of the Year, DeGrom, 2014 National League Rookie of the Year, Matz and Syndergaard were all central to the Mets’ 2015 World Series run.

In the 2016 season, prospects Seth Lugo and Robert Gsellman filled gaps in the rotation to carry the Mets to a Wild Card game berth, both boasting sub-three ERAs down the stretch. To complement the Mets’ stellar pitching, Alderson has mostly acquired older, more established position players on short-term deals.

But while the Mets have made the playoffs on the backs of their pitchers the last two years, frequent injuries plaguing their young arms have stagnated the team’s progress. Matz, Harvey, Wheeler and DeGrom have all had Tommy John elbow surgery at some point in their career. Wheeler missed the entire 2016 season recovering from the injury, Harvery missed most of the season recovering from the second major surgery of his career and Matz landed on the 15 day disabled listed with left shoulder tightness in August. Matz is currently day-to-day with a sore left elbow.

Building an MLB team around young pitching might work out in the short term, but the risk is significant. A 2012–2013 survey discovered that 25 percent of active MLB players had undergone Tommy John surgery at some point in their careers, a procedure that often takes over a year to recover from and fails 20 percent of the time. Also, according to a study of all MLB players from 2002–2008, pitchers are 34 percent more likely to be injured than position players.

Cubs President of Baseball Operations Theo Epstein has taken the opposite approach to Alderson, crafting his team around young hitters and pitchers on short-term deals. Since leaving the Boston Red Sox for the Cubs in 2011, Epstein has traded for youthful prospects such as Anthony Rizzo and Addison Russell and drafted Kyle Schwarber, Kris Bryant and Javier Baez. Rizzo, a three-time All Star, and Bryant, a two-time All Star and 2016 MVP have turned into superstars while Schwarber, Russell and Baez look to be stars in the making.

“You can never have enough pitching” is a phrase repeated ad nauseam in baseball lore. There is undoubtedly some truth to the saying. Young, cheap, team-controlled pitching is hard to come by. A shutdown pitching staff like the Mets’ is devastating to opposing teams’ psyche. Sweeping a team during the regular season with a string of aces seems impossible to pull off consistently. An offense’s production waxes and wanes considerably while a pitching staff’s production is much steadier.

“If the injury risk increases, or is at a very high level, I’m not sure why that suggests you should have less, rather than more, pitching,” Alderson has said about building teams around pitching. “From our standpoint, I think it validates the notion that you can never have too much. It’s been true forever in baseball, and I think it’s probably more true today.”

But as Epstein has proven, a team built around young hitting can still have a quality pitching staff. Epstein has acquired veteran pitchers such as Jake Arrieta, Jon Lester and Aroldis Chapman through trades and the free-agent market. And because these pitchers are on short-term deals, they do not carry as big a risk as the long-term investment of a young pitching prospect under team control for six years.

Two years ago, the Mets and Cubs met in the National League Championship Series. The Cubs’ hitting was no match for the power arms of the Mets’ pitching staff as New York swept the Cubs in four games. Last season, the Mets won the season series matchup against the Cubs 5–2, but they did not meet in the playoffs. Perhaps 2017, a year when both teams are expected to excel again, will be the season the debate over how to best build a team is finally decided.