But as the regular season enters its waning month, that possibility has become quite real.
All that separates it from winning the conference are a few tweaks.
The Celtics' slump can partially be blamed on its battle with the injury bug—particularly forwards Jae Crowder and Kelly Olynyk. Both will need to be healthy for the playoffs.
Olynyk, who missed over a month with a shoulder injury, finally returned to action in the team's Wednesday night loss to the Oklahoma City Thunder. It'll take a few games for him to find his stroke again, and Boston sure could use the boost—he's shooting a career-high 40.8 percent from three-point range this season.
Crowder's status is less certain, as his ankle injury is believed to have him out for a few weeks. His absence has clearly hurt the Celtics.
The 25-year-old has drawn Draymond Green comparisons, as SB Nation's Mike Prada noted, which are well-deserved, for his performance this season. He has set career highs in every major category, including his 14.4 points-per-game average.
Ideally, Boston would be completely healthy for the final few games of the regular season, so it can regain its chemistry for the playoffs. Barring an unforeseen setback for Crowder—or a severe injury to another player—this certainly appears to be the case.
The Celtics have counted on stellar play from their guards all season to fuel their success. The backcourt trio of All-Star Isaiah Thomas, Avery Bradley and Marcus Smart average over 40 percent of the team's points per game.
If Boston can get similar success from its frontcourt, that would significantly boost its playoff chances.
Jared Sullinger has emerged as the team's best all-around big man this season, indicated by his near- double-double average. If he can increase his jump-shot success, it would be an increased burden on opposing defenses.
Another player to keep an eye on is Amir Johnson, Boston's starting power forward. Though his minutes are limited in the midst of the Celtics' forward rotation, he needs to make every minute count.
When looking at the Celtics' potential matchups in the playoffs, it becomes apparent the East is loaded with talented big men. The Atlanta Hawks have Al Horford, the Toronto Raptors have Jonas Valanciunas and Cleveland has both Kevin Love and offensive-rebound machine Tristan Thompson.
In order to best these teams, Boston's big men will need to rival their tenacity and effectiveness on both ends of the floor.
Isaiah Thomas: Superstar
Every successful playoff team has a go-to guy—the team's clear leader who can create a big play when it needs one most.
For the Celtics, that comes in the form of a little guy with a big heart: the 5'9" Isaiah Thomas.
Thomas has been everything for the Celtics, including the source of some incredible plays that have Boston fans seeing the reincarnation of vintage Rajon Rondo:
In the playoffs, Thomas will have to remain the focal point of the Celtics offense. He has a tendency to get a bit reckless with his shot selection at times, so he'll need to be a little more disciplined on possessions.
But ultimately, his high-energy style of play wears down opposing defenses, giving the Celtics a major advantage late in the game.
With the No. 3 through No. 6 seeds in the East separated by a mere 0.5 games, Boston faces a wide variety of playoff scenarios.
If the playoffs were to begin on Friday, the No. 4 Celtics would host the No. 5 Miami Heat. Should Boston win that series, it would most likely have to face the Cavaliers in the semifinals.
Conversely, regaining the No. 3 seed would give Boston a home series against the No. 6 Charlotte Hornets. A victory in that series should pit them against No. 2 Toronto.
The latter scenario appears to be the more favorable option, even though the white-hot Hornets have won 15 of their last 18 games. Facing the Raptors would give another team the opportunity to defeat (or at least wear down) the Cavaliers, which would help Boston greatly in another potential Cavaliers-Celtics Eastern Conference Finals matchup.
Toronto relies heavily on elevated production from their two All-Star guards: Kyle Lowry and DeMar DeRozan. Fortunately, this plays right into the Celtics' hands.
Bradley is arguably the league's best perimeter defender, and Smart isn't too far behind (though he needs to keep his aggressiveness in check). Both will need to stay out of foul trouble.
If the Celtics can limit both Lowry and DeRozan, Sullinger and Tyler Zeller will need to contain Valanciunas down low. Forcing the Raptors to draw increased scoring from their bench gives Boston a sizable advantage.
Against Cleveland, the focus isn't quite the same.
Thomas will become increasingly important on offense, especially if he can beat Kyrie Irving on drives to the hoop. Of course, there is the possibility Bradley is asked to guard Irving, which bodes well defensively.
But unlike the Raptors, the Cavalier forwards play a very significant role in the offense. LeBron James is obviously the No. 1 priority on both sides of the ball, but Love can pose a major disadvantage for Boston. The Celtics will need to prevent him from getting open looks on three-point shots.
Assuming Crowder heals on (or ahead of) schedule, he'll be given his desired task of guarding James, as Taylor C. Snow of Celtics.com pointed out. As for Love, the Celtics will likely mix things up. Olynyk, Johnson and perhaps even Jonas Jerebko will be assigned to Love at various points.
Overall, the Celtics are fully capable of winning the Eastern Conference. The talent is absolutely there, and their great depth gives them a big advantage over just about any NBA bench.
If they can get healthy and see some increased contribution from a handful of players, the Celtics could take trip No. 22 to the NBA Finals.