Anybody who picked the Boston Celtics to make the playoffs last year, even in a weakened Eastern Conference, would have been called crazy. Speculation all throughout the beginning of the season revolved around Rajon Rondo and when he would be traded. That trade happened in December to the Dallas Mavericks and it looked like the Celtics had thrown in the towel on the season. But even with rookie guard Marcus Smart leading the charge, the Celtics remained competitive. In mid-February Boston acquired Isaiah Thomas from the Phoenix Suns and his emergence to the team helped push them into the playoffs.

Fast forward to present day the Celtics are looking to build off the surprise playoff appearance last season, but the way they are looking to build off that success is by building a team that goes against the direction the rest of the league is going. From LeBron James, to Tim Duncan and Stephen Curry, the NBA’s elite teams are revolved around a star player. The Boston Celtics don’t have a “star player” on their roster. What they do have, though, is a core group of talented role players led by a coach who has time and time again taken that mediocre talent and transformed it into a competitive team.

For all this to happen the Celtics need a leader, somebody they can turn to late in games and look towards to take over. Who better to give this role to than the player who was the driving force of the Celtics’ run last season. Isaiah Thomas arrived to Boston last February and immediately produced. Thomas averaged 16.4 points last season all coming off from the bench. His ability to operate the pick-and-roll and quickness to get to the basket allowed the Celtics to have an offensive player they could play around. In Round 1 of the playoffs against the Cavaliers, Cleveland knew Boston’s gameplan with Thomas on the pick-and-roll and would trap him whenever the pick was set. Thomas struggled with the pressure of the trap and this caused Boston’s offensive attack to suffer and helped Cleveland achieve a quick four game sweep.

Coming into this season the Celtics want Thomas to adjust more in the heat of the game with the pick-and-roll than he did last year. Forward Jae Crowder told Boston media at camp on Thursday, “Our way of adjusting is (Thomas) trying to find other guys and trying to make a play for him, not necessarily (Thomas) making a play for us each and every time.”

Already, head coach Brad Stevens sees an astounding improvement in Thomas’ game. “(Thomas) has completely been unbelievable on offense, which tells you all that he’s doing for everybody else,” Stevens said. “He’s playing very unselfish. He’s making the right read regardless of situation, and he’s not forcing anything.”

This hasn’t been a situation either where Stevens has asked Thomas to score less or shoot less. This has been Thomas all on his own making these adjustments entering the season. But Boston will still need Thomas to be the team's scoring attack, and by surrounding him with some top tier three-point shooters, Stevens is hoping this will allow Thomas, along with Marcus Smart, to be an all-around playmaker as well.

Boston made a smart decision resigning Jonas Jerebko, a player they received in a trade with the Pistons, in the offseason to a two-year deal. The Swedish Larry Bird, as GM Danny Ainge likes to call him, doesn’t score a lot of points, only averaging 7.1 points a game with Boston, but his 40.6 percent beyond the arc makes him an obvious scoring threat.

The Celtics also signed Amir Johnson in the offseason to a two-year $24 million deal. The former Toronto Raptor is an athletic 6’9 center/forward who plays excellent defense. His presence with the pick-and-roll for Boston this season will come as great use to the offense. He also has the ability to step out and hit the 3-point shoot, shooting 41.3 percent beyond the arc last season.

Stevens has been impressed by Johnson and commented on his defensive ability saying, “first of all, he's 6-9, he's long, he's athletic. But then I think there's not a lot of people like that generally, but there's a lot of people like that in this league. But his mind is excellent for defense and he really prioritizes it. And then his motor is extremely high. So I think that all that factored in is why he's separated himself as helping your team win when he's on the defensive end of the floor.”

Another inside force the Celtics have to play with this season is veteran forward David Lee who Boston got in a trade during the offseason with Golden State. Stevens already has found a liking to Lee calling him a “playmaker” and a “point-forward” who has shown early in camp the ability to distribute the ball to open shooters. When Thomas is on the bench the Celtics do tend to play their offense through their big men and Lee possibly could be a part of that offense.

Boston also will need both Avery Bradley and Jae Crowder to improve their scoring ability this season. These two players have the talent to help Thomas or Evan Turner score on the offense and will need contributions from them each night.

Even despite Thomas’ evident impact he has when he is on the floor, it still looks like Stevens will go with Marcus Smart at the starting point guard position. Smart in his rookie season averaged 7.8 points a game and 3.1 assists. Both him and the Celtics have already discussed in camp that he needs to be more of a facilitator and playmaker on offense this season.

On the rookie side of things they doesn’t appear to be one who will make an immediate impact.

The Celtics first selection in last years draft, Terry Rozier, has already gained high praise from Ainge with his quickness and has caught the eyes of the veteran players. That quickness could have some effect when operating the pick-and-roll but the extent Rozier’s playing time will depend on the players ahead of him.

Jordan Mickey, who Boston also received in the draft, has been extremely impressive and Stevens on multiple occasions has called him the best shot-blocker and defensive rim protector on the team. Boston’s bigs struggled a bit last season on the defensive side of things and Mickey could help improve that the more he progresses.

And then you have the Celtics last pick up in the draft, sharpshooter R.J. Hunter. Evan Turner, who has gone up against Hunter one-on-one at times in camp, says he has been very poised and has a great competitive edge to him, along with that shooting stroke.

So as you look down the Boston Celtics roster you, again, see no real “star player.” The core group of role players, though, is hard to miss. The addition of Johnson and Lee, the continuous solid play from Thomas off the bench, along with Smart finding his niche on the offensive end could lead Boston to another playoff appearance in 2015/16.

Brad Stevens, though, has his hands full once again of trying to turn a group of mediocre players into something special.