The Boston Celtics are poised for another step upwards this season. Adding big man Al Horford in free agency will give them a huge boost. They missed out on Kevin Durant and might have failed to make a big trade around the draft but it was always more important that they didn’t make any big mistakes, like committing too much money to the wrong players.

The goal for this season is obviously to win at least one playoff series and Al Horford is close to the perfect addition to the roster to achieve that. The Celtics have lacked a big man who can both be a primary scoring option if needed and be the anchor of a very aggressive defense. Coach Brad Stevens has spent a lot of time in the previous seasons tinkering with his lineups to find the right balance but this season he should be able to use his starters as his go-to unit also for closing out games. Though we’ll probably still see some substitutions dependent on match-ups.

The starting five as expected

Isaiah Thomas made the All-Star team for the Eastern Conference last season and was arguably the Celtics most productive player on offense, creating both for himself (22.2 points/game) and others (6.2 assists/game). He is still the weakest link on defense among the starters but that’s not as bad as it sounds. The Celtics still play great team defense when he’s on the floor because they have stalwarts like Avery Bradley and Jae Crowder in the lineup.

Bradley became the second Celtics player to receive honors last season when he made All-Defensive 1st Team, his second Defensive Team selection in his career. He has set his eyes on Kawhi Leonard’s Defensive Player of the Year spot in this season, though that’s a lofty ambition. Bradley has improved his game on both ends every season he has been in the league and entering his 7th season, he is not only the undisputed veteran (no one else has been longer than three years with the team) but also a very valuable player.

If his improved offensive game carries over from pre-season he might have transformed himself from a 3-and-D specialist to an almost complete player who can also be a playmaker for himself and others.

Jae Crowder was one vote from making the All-Defensive 2nd Team last season, beating among others LeBron James in the election. The Celtics were doomed in the Atlanta series when Crowder got injured right before last season’s playoff and only returned as a much-hampered version of himself. He used last season to establish himself as a starter in the league and during pre-season he has shown that he might be even better this season.

Al Horford was probably the Celtics’ biggest free agent acquisition in franchise history and the expectations for the Dominican big man were and are high. All through pre-season, he has shown everything that the Celtics want from him except being a go-to guy when the game is on the line, that has to wait until an important game is actually on the line.

Amir Johnson has so far grabbed hold of the fifth spot in the starting line-up and he may keep it through the season, depending on how Kelly Olynyk fits in with the new rotation when he is ready. Johnson has looked very comfortable in pre-season and seems to be injury free, a good sign for the season.

Kelly Olynyk hasn’t been able to practice with contact yet, but that’s according to schedule after his shoulder injury. It’s an important season for Olynyk. He has already proven his worth as a match-up problem for most bench units, but he has yet to be consistent enough to be a key player for a good team.

Marcus Smart is "the sixth starter"

Brad Stevens has called Marcus Smart ”the sixth starter” on the team, which doesn’t make sense if taken literally. But Smart has shown that he can play with and against the best lineups the pre-season has offered. He seems to have improved his mid-range game but the three point shot that he’s been working on this summer hasn’t been falling.

When Smart plays with the second unit he shares ballhandling responsibilities with Terry Rozier, who has been a revelation since his breakout performance in limited minutes in the first round series against Atlanta in the spring. Through Summer League and pre-season Rozier has often been the best player on the court and the biggest scoring threat for Boston’s bench.

Jaylen Brown is the youngest player on the roster and he comes with both question marks and big expectations. He makes rookie mistakes on both ends of the floor but has already wowed the fans with his athletic plays, something that hasn’t been prevalent in Boston since the last time Gerald Green was around.

Green has been around the world since then but now he’s back as a wing backup and scoring punch off the bench. Green is a constant threat even on nights when he is not effective and on some nights he can take over a game. He hasn’t been at his best this pre-season but he fits well with what the Celtics are trying to do.

Jerebko is an underrated signing

In the playoff series against Atlanta, Jonas Jerebko showed why he might be the most underrated signing for the Celtics in recent years. When he replaced Sullinger among the starters he added two things to the lineup: three-point shooting and versatile defense, two of the main ingredients in the modern small ball. His value is lower when he is used in more traditional lineups or when he is the only three-point threat on the court so the defense doesn’t give him open looks.

One of the last signings for Boston this summer was Tyler Zeller who has been struggling ever since Rajon Rondo was traded almost two years ago. Zeller thrived in a short time frame, playing pick-and-roll and pick-and-pop with Rondo, but has since then looked like a career backup, big man. To his credit, he has delivered when called upon even if he has been out of the rotation for a while. He has looked pretty bad this preseason until Monday’s game against Brooklyn, but he is still valuable for two reasons: He is reliable and his contract is the perfect filler if a trade comes up.

On the bubble

18 players have (partly) guaranteed contracts for the season. But in the end, it will come down to who gets the 15th spot between R.J. Hunter and James Young. Neither of them has proven that they belong in the NBA, yet, and this is the reason why Gerald Green was brought in as a scorer for the bench.

The decision between Hunter or Young is probably the biggest roster headache for Ainge and Stevens. Young is still the second-youngest player on the roster, but on the other hand, he has had two seasons, while Hunter only has had one to prove his worth.

Hunter is more versatile on offense and shows great basketball IQ but he gets easily bullied when the game gets physical and you have to wonder whether he will ever get strong enough to hold his own. And while Young has shown promise as a 3 point shooter in the D-League, Hunter’s numbers have been close to abysmal both in the NBA and in the D-League. Young has also gained enough muscle to hold his own much better than he did as a skinny teenage rookie.

Both have shown potential, though, so it probably comes down who has the better upside.

Ben Bentil, drafted this summer with pick no. 51, was expected to be a bubble player, too, but he’s not going to make it. He has barely gotten any minutes this pre-season, a clear sign that he’s out of the picture.

Rookie point guard Demetrius Jackson and second-year big man Jordan Mickey could also be on the bubble, but they have the advantage of providing skill sets that fit into Stevens’ basketball philosophy, Jackson as a ball-handler, and Jordan as a rim protector who is fast enough to defend most guards, too.

According to Jay King of MassLive.com the decision hadn’t been made on Monday, and Brad Stevens explained that the discussion was ongoing:

”Obviously we have conversations all the time, but we have not gotten to the point where we're talking finality on anybody, in large part because everybody has played very well or shown great strides,” said Stevens prior to the penultimate pre-season game against the Brooklyn Nets.

GM Danny Ainge obviously hopes to consolidate the roster with a trade before the regular season starts so that he doesn’t have to give up a player without compensation.

Time to get excited Celtics fans

While the Celtics can be considered overachievers the previous two seasons when they reached the playoffs, anything lower than a top four in the Eastern Conference and advancement to the second round this season could be considered a failure or at least a disappointment.

The Celtics might not be ready to compete with the NBA champions from Cleveland, but with loads of young talent to develop through the seasons, players stashed overseas and possible high draft picks from the Brooklyn Nets the next couple of years there is no do-or-die future for the team. They are set up for success no matter what happens this season. And if an exceptional player becomes available in trade, the Celtics have the assets and contracts to get it done.

The team said goodbye to...

  • Jared Sullinger (Celtics renounced rights before he signed with the Toronto Raptors)
  • Colton Iverson (gave up draft rights)

While Iverson never really stood a chance to make the team, Sullinger was the player with the second-longest tenure after Bradley. It seems like ages ago, but he played with Kevin Garnett and Paul Pierce in a very promising rookie season.

But there were signs that he had overstayed his welcome in Bean Town. Ainge had two seasons in a row made it public that Sullinger hadn’t reached his weight goals entering training camp. And the Celtics had shown no interest in giving Sullinger the max extension of his rookie contract that he and his agent had wanted.

Under other circumstances, Sullinger would leave a gap behind him but the signing of Horford also solved that problem.

Stashed overseas and in Maine

  • Guerschon Yabusele (drafted #16/2016, plays for the Shanghai Sharks in China)
  • Ante Zizic (drafted #23/2016, stays with Cibona Zagreb in Croatia)
  • Abdel Nader (drafted #59/2016, expected to sign with the Celtics’ D-League affiliate, the Maine Red Claws)
  • Marcus Thornton (drafted #49/2015, plays for Victoria Libertas Pesaro in Italy)

Both Yabusele and Zizic have received rave reviews for their play so far. The Chinese league hasn’t started yet, but Yabusele proved that he’s in excellent shape when he played 44 out of 48 minutes in a pre-season game against the Houston Rockets, scoring 24 points and grabbing 12 rebounds. Yabusele is a possible late season addition for either the Celtics or the Red Claws since the Chinese regular season ends mid-February.

Zizic has so far been dominant in the Adriatic League (ABA), which is a regional that covers former Yugoslavia with wild card teams from several other countries. Zizic has an impressive PER of 30.57 through the first five games of the season.

Nader agreed to take a contract in Maine this season while hoping for an opening on the Celtics roster. This way the Celtics maintain his draft rights (as they do with the other stashed players), which is probably his best shot at an NBA career. Nader had an impressive Summer League but the Celtics were already overloaded with guaranteed contracts.

Thornton, on the other hand, failed to impress in Summer League and unless playing in one of the stronger leagues in Europe gives him a strong push in the right direction that might have been his last shot at making it at least to training camp.