By Matt Gregan, Sports Talk Philly Editor 
The Philadelphia 76ers used free agency to rebuild their team for the second season in a row. They added big names like Al Horford and Josh Richardson while subtracting some of their best players last season, Jimmy Butler and JJ Redick. All the while, Ben Simmons and Joel Embiid, the team's two superstars, have been the constants through all the change over the past few years.
One of the things that made Butler such an integral piece to the 76ers' team that made it to the second round of the Eastern Conference playoffs last season was his ability to close games. Butler had the rare combination of being clutch on the floor and being aggressive with the ball at the end of games. He averaged 6.4 points per game in the 4th quarter of games as a member of the Sixers last season, good for 12th best among qualifying NBA players. The ability to close games is an important skill to have in the NBA. Butler's abilities late in games will be hard to replace for the Sixers.
The 76ers currently have no clear closer. The closer role is there for someone to step up and take it. Embiid has potential to be the team's closer (6.3 points per game in the 4th quarter last season). Simmons could further develop his offensive game and become more aggressive to help out late in games. However, he often disappears late in games because of his lack of a perimeter game combined with his struggles at the free-throw line. The Sixers will need someone to step up and take control of games in the 4th quarter, regardless of who that person is.
The additions of Horford and Richardson both improve the 76ers, but both of those players are role players who fit in nicely as complementary players with Simmons and Embiid.
Horford is the prototypical complementary player. He can do a bit of everything, and he doesn't require having the ball in his hands very much to have success. He took 10.6 shots per game last season, and has shown over the last couple of years that he is fine with not being one of the main options on offense.
Richardson was given the chance to be the main option last season for the Miami Heat, and he set career highs in most statistical categories. However, his shooting efficiency was down drastically from where it was at previously (45.1 field goal percentage two years ago to 41.2 percent last season). It should benefit both Richardson and the 76ers to have him take less shots but shoot at a higher percentage, similarly to what he did in his first three years with the Heat. He fits in with the Sixers as a defense-first player who is able to provide some offense in the form of his outside shooting and slashing abilities. Simmons, Embiid and Tobias Harris all should be taking more shots than Richardson.
The big moves that the Sixers made in free agency were all centered around the development of the superstar duo of Simmons and Embiid. That duo contains a lot of talent, but both players have key areas of their game to work on this offseason.
Simmons needs to work on adding some semblance of an outside shot to his game. He will continue to hold both himself and the rest of the team back until he adds an outside shot, something that will completely transform his game and the way that teams defend him on the court.
Embiid needs to work on changing his lifestyle and getting into a better physical condition. The playoff series against the Toronto Raptors, one in which Embiid was hampered by poor health for all but one game, showed why Embiid needs to work on becoming a better athlete and staying healthy. He already has MVP-caliber talent, but his poor health and conditioning is holding him back from truly becoming one of the NBA's top players.
Until both of the Sixers' young superstars make those necessary improvements, the team's ceiling is limited. No matter who is surrounding them on the team, it all comes down to how good Simmons and Embiid can be.
