The Philadelphia Phillies had a busy offseason to significantly improve their ballclub, and as a result, Fangraphs has the Phillies as the second best team in the division with a 48.3 percent chance of making the postseason. On paper, there is a lot to get excited about with the Phillies.

By signing Andrew McCutchen and Bryce Harper, the Phillies have added two potential future Hall of Famer outfielders. With David Robertson, the Phillies have added a closer with World Series experience and, beyond that, the Phillies have vastly improved an MLB worst defense (-146 DRS).

Rhys Hoskins has moved from left field (-24 DRS) to first base. While McCutchen is no longer a center fielder, he was a solid corner outfielder last year (2 DRS). In place of Scott Kingery (-6 DRS) at short, the team has Jean Segura (5 DRS). That is a significantly improved defense, especially if Harper, Cesar Hernandez, and Odubel Herrera return to their 2017 levels defensively.

This should make the Phillies pitching better, but it’s not a foolproof measure to improve the Phillies pitching, which is one of their biggest question marks heading into the season.

Atop the Phillies rotation was Aaron Nola, who actually had a higher bWAR than Jacob deGrom and Max Scherzer last year. At 26, it would seem like this is where his career takes off. It’s also possible Nola’s .251 BABIP and 82.5 percent strand rate is not repeatable, and his true talent level is the roughly league average pitcher (106 ERA+) he had been over the prior two seasons.

The Phillies number two starter, Jake Arrieta, is not the pitcher he once was. After a strong start to the season, he had a 5.04 ERA in the second half last year. That’s all the more troubling when you consider Arrieta is 33, has had a 3.50+ ERA in each of the past two seasons, and has typically been a second-half pitcher in his career.

Behind their top two, the Phillies next three starters had an ERA of 4.36 or above with an ERA+ of 95 or below. With the J.T. Realmuto trade, the Phillies do not have the organizational depth to call up a Sixto Sanchez to help bolster the rotation.

Speaking of Realmuto, he is no doubt a tremendous hitter, and he should be even better hitting in Citizen’s Bank Park instead of Marlins Park. Still, he’s not going to help his pitchers the same way Jorge Alfaro did. According to Stat Corner, Realmuto has historically been one of the worst pitch framers in baseball while Alfaro was league average.

Now, while Baseball Prospectus doesn’t have Realmuto that low, it did have Alfaro as the ninth best pitch framer last year. That’s going to hurt a pitching staff which was already the Phillies biggest question mark to enter the season.

Another significant issue is Gabe Kapler‘s leadership. Early in the season, his communication with players was put into question with Nick Williams complaining about how computers were driving the decisions. Recent reports indicated part of the reason the Phillies fell out of contention last year was the team playing Fortnite during games. The only player who did anything about it, Carlos Santana, was traded away during the offseason. That’s all before the issues Nick Francona brought to light about Kapler’s tenure as the Dodgers’ Director of Player Development.

This Phillies team is going to need strong leadership too. In 2015, Jonathan Papelbon choked Harper as part of an altercation the two had. Last year, Dee Gordon and Segura got into a fight in the clubhouse. Arrieta has been known to be intense as evidenced by his ripping the team last June. Fair or not, these are big personalities, who have had clubhouse conflicts.

Now, the Phillies are immeasurably better on paper. Their defense is better and their lineup is deeper and among the best in the National League. A very promising bullpen with Seranthony Dominguez, Pat Neshek, and Edubray Ramos also now has Roberston. They have players with postseason and World Series experience.

This is also potentially a powder keg with poor leadership. It is built on questionable pitching and, while the defense is better, it could still be among the worst in the majors.

In the end, after all the improvements, they may find themselves needing to out-slug the teams in their division who, arguably, have lineups equally as good, better defense, superior pitching, and stronger leadership.