The Boston Celtics reached the midway point of the 2013-14 campaign with Friday's loss to the Los Angeles Lakers, scooping up Rajon Rondo while whizzing past the midseason checkpoint.

The trade deadline looms a month away and the Celtics have already swung two deals in two weeks with eyes toward the future. Celtics president of basketball operations Danny Ainge stressed that there's still plenty of work to do to navigate this transition period and Boston is likely to further tinker with its roster if the right deals are available.

But even beyond the Feb. 20 trade deadline, the final three months and final 40 games of the 2013-14 season will play a big role in determining how this team will look in the future. This is a chance for Ainge, his staff and coach Brad Stevens to determine which players currently on the roster have long-term futures here.

"I feel like we're figuring out who we want on the bus," Ainge said last week.

As this bus rolls through the midseason toll plaza, we offer our midpoint evaluations while trying to gauge where players are currently seated on this bumpy ride.

As always, a reminder that grades are offered based in large part based on expectations.

ON THE BUS

These players appear to be part of Boston's long-term future given their performance, age and contract status:

Despite just recently returning to action, captain Rajon Rondo has done everything he can to help the Celtics so far this season. AP Photo/Charles Krupa

• Rajon Rondo: Despite only recently returning to game action, Rondo had a phenomenal start to the season. He did his part in establishing an immediate relationship with Stevens, diligently navigated his rehab without rushing the process, showed his leadership by accompanying the team for nearly every game and practice, and found time to immerse himself in the community (reflected in winning the league's Community Assist award for December). Added all up, it was enough for the Celtics to bestow upon Rondo the crest of captain, an honor that suggests he's not just riding the bus, he just might be Stevens' co-pilot. Unless the wheels come off, it appears the Celtics are committed to Rondo as the centerpiece of this rebuild, which puts a long-term contract extension near the top of the priority list in the near future. [First-half grade: A]

• Jared Sullinger: Off-the-court issues could have derailed his sophomore season before it began, but Sullinger apologetically navigated that process and has been a star pupil on the basketball court. A hand injury contributed to a holiday slump, but Sullinger's play has suggested a high ceiling even as he bounces back from back surgery. He's a team-best plus-34 in plus/minus, the only regular in the positive -- and that's even more incredible when you consider that Boston's four other most-used starters in the first half were an average of minus-126.8. Sullinger can get in better shape, he can play better defense, but getting a legitimate center alongside him would help matters, too. The only reason Sullinger wouldn't stick on the bus is if he were used as the Al Jefferson-type centerpiece of a deal for a superstar. [First-half grade: B+]

• Kelly Olynyk: Expectations were set unfairly high after the 7-footer had a sensational summer league debut. The Celtics like a lot about the 13th overall pick in June's draft, having moved up three spots to snag him, but he's got a lot of development ahead, particularly on the defensive end. Like Sullinger, Olynyk could be utilized as a trade chip if Boston were seeking more established help by combining its assets (young players and draft picks). But we've seen encouraging glimpses from Olynyk, particularly recently, which suggest that he can be a core member of this team moving forward. [First-half grade: C]

• Phil Pressey: This pint-sized undrafted rookie free agent has seen his confidence grow and, with a recently thinned-out backcourt and Rondo on a minute restriction early in his return, Pressey is getting an extended opportunity. He's responded by showcasing his quarterbacking skills (94 assists vs. 25 turnovers this season) and being a competitive defender (he owns the team's best defensive rating among regulars). Pressey needs to develop a consistent jump shot (he's shooting 23.2 percent overall; 16.7 percent from 3-point land) to keep defenses honest, but he's a super low-cost body with a defined skill set that Stevens can confidently call on. [First-half grade: C+]

• Vitor Faverani: His 12-point, 18-rebound, 6-block effort in Boston's home opener seems another lifetime ago. Faverani started fast and came screaming back to earth. Boston's crowded frontcourt and his own inconsistent defense have limited his playing time. The deadline could open up a greater opportunity for the 25-year-old Brazilian big man, who might just need more minutes to find his way again. The Celtics have him under their control at low money ($2.1 million next season) moving forward. [First-half grade: C-]

TICKET TO RIDE

These players have a spot reserved on Boston's bus, but there are obstacles to keeping them on board (or getting them off, in some instances):

Avery Bradley has played well enough to reserve a seat on the team bus for a while. Craig Mitchelldyer/USA TODAY Sports

• Avery Bradley: Boston's most consistent two-way player this season, Bradley has seen his offense flourish even further removed from double shoulder surgery. Bradley is averaging 14.8 points per game on 44.1 percent shooting, thriving in the midrange while re-establishing his 3-point shot. His defensive rebounding has spiked as well, and while his individual defensive numbers aren't quite as glossy as in recent seasons, he's put an increased focus on team defense and should benefit at both ends of the court from the return of Rondo. If the Bradley-Rondo combination thrives, it will make it easier for Boston to stomach the hefty pay raise that Bradley will soon command (after failing to hammer out an extension in October, Bradley will be a restricted free agent with a $3.6 million qualifying offer, but could draw higher offers from around the league). [First-half grade: B]

• Jeff Green: Green has been exactly who he has been over the first six years of his NBA career, which is sort of the problem. Thrust into the spotlight with Rondo rehabbing and Boston's veterans departed, Green was supposed to flourish as the focal point of the offense. Instead, his per-36-minute numbers remain in line with his career averages, his scoring up a bit (17.1 points per game), but his field goal percentage down (42.9 percent). His defense has been better, but the Celtics are still waiting for Green to be the sort of offensive player they can lean on every night. He is owed two years and $18.4 million after this season; is it in Boston's best interest to ride it out with Green? [First-half grade: C]

• Kris Humphries: It's unfair that Humphries' best ball has coincided with Boston's recent struggles. It's not the fault of a player who is thriving on pure energy and effort. Boston's offense is five points better per 100 possessions with Humphries on the court, and the defense is a half-point better, too. Humphries tops the team with a defensive rebound rate of 24 percent, and a total rebound percentage of 17.2 percent. He is the sort of player whom a contender might love to add for a playoff push. The question is whether a contender can offer something better than the cap space Boston is set to receive. And consider this: Might Boston prefer to keep Humphries for the chance to bring him back next season? Would the mid-level exception be enough to keep the veteran big man around? The Celtics have shown in recent years that there's a lot worse ways to spend it. [First-half grade: B+]

• Jerryd Bayless: Acquired from Memphis while dealing away Courtney Lee's bloated contract, Bayless added another ball handler to Boston's bench (and the potential for scoring in spurts). Bayless is an expiring deal and an NBA vagabond, but that wouldn't preclude the Celtics from bringing him back on a low-money deal next season. He's only 25 and will have the chance to plant some rare NBA roots if he shows he can be an asset off the Boston bench. [First-half grade: Incomplete]

• Gerald Wallace: Wallace's contract was the cost of doing business with the Nets this summer. By taking on his inflated deal, the Celtics were able to maximize the return on Paul Pierce and Kevin Garnett. Trouble is, there's no easy way to shed the two seasons and $20.2 million remaining on Wallace's deal after this season. Boston's only hope might be to dangle him and some collection of future draft picks to a team that can absorb his deal (or is more willing to ride -- or stretch -- it out). Wallace's postgame rants have gotten tired, but he's still a quality veteran presence whose skill set is simply no longer on par with his pay rate. Beyond some griping, he's been a good veteran and an excellent inbounder, but we still expected more from Crash on the court. [First-half grade: D+]

• Joel Anthony: The seventh-year big man was acquired from Miami as part of the deal that sent MarShon Brooks and Jordan Crawford to Golden State. He hasn't played yet for Boston and its already overcrowded frontcourt, but could provide some needed interior defense if he gets an opportunity. The Celtics would probably prefer he test free agency, but Anthony has a $3.8 million player option that he'd be foolish not to trigger this summer. If the Celtics don't see a long-term future with him, he's going to have to be bundled to get off the bus. [First-half grade: Incomplete]

EXIT APPROACHING?:

Who might be next to go in Boston? These players are the favorite in the clubhouse given their contract status: