Midseason questions for Celtics

The Celtics make the turn to the back nine of the NBA regular season Friday night when they welcome the Utah Jazz to TD Garden to cap a six-game homestand. With half of its 82-game slate complete, Boston boasts a glossy 32-9 record -- the best mark in the Eastern Conference -- and has positioned itself well as the jockeying begins for playoff seeding.

Most impressively, the Celtics have done it amidst a never-ending flurry of injuries, which leaves coach Doc Rivers wondering what his team's true potential is when -- or maybe "if" is the better word -- his team can get healthy.

"Record-wise, obviously, I'm happy," Rivers said before Wednesday's win over the Detroit Pistons. "You always think you should have won more games. But you never count the ones you probably should have lost, you only count the ones you probably should have won. So I'm happy that way, but we don't know yet, team-wise, [because] we haven't really had [a healthy roster] and I don't know how much that will impact us later.

"You just want to keep getting better and we see small signs of that, at least with our second unit. With guys out, we've never had the chance to work [at full strength] so far, and that's the only area of concern for me. We really haven't gotten the second unit as a group yet. All that missed time, I don't know what that will do to us later."

Rivers isn't the only one with questions. In our midseason mailbag, we tackle the five most commons questions we've heard from fans in recent days (non-Rasheed Wallace-related questions, at least):

Q: I keep hearing the Celtics rank 30th in the league in rebounding. Is that true? I thought Boston's rebounding numbers had improved from last season? Rebounding cost us Banner 18 in last year's Finals!

A: The Celtics do indeed rank dead last in the NBA in total rebounds, hauling in a mere 1,567 caroms through 41 games (38.2 per contest). But looks can be deceiving.

Dig deeper and you'll see Boston ranks 18th in defensive rebounds (1,252) and much of its low overall rebounding output stems from an indifference toward offensive rebounds (a league-low 315, with 29th-ranked Dallas boasting nearly 50 more offensive boards through the same amount of games).

A better stat to gauge Boston's improvement is defensive rebound percentage, which quantifies the percent of available rebounds a team is corralling. Boston ranks eighth in this category (75.2 percent), a mere fraction of a point from shuffling up two spots and joining San Antonio and Miami (75.3 percent).

"We've been up and down the last couple weeks, and we've had bad rebounding nights and won games, but overall our rebounding numbers are OK with us," Rivers said last week before getting the team's top rebounder -- Kevin Garnett -- back from injury. "The one number that's overplayed is offensive rebounds. We're not big believers in offensive rebounds because, if you get back every single time, you probably save more points in the long run. That's not a concern to us; it's the defensive rebounds that are a concern."

Thanks in part to a rejuvenated Shaquille O'Neal, the Celtics boasted a 47-34 advantage on the glass in Wednesday's win over Detroit, snatching up an eye-popping 14 offensive rebounds (roughly 4.4 percent of their season total).

Q: Even if Jermaine O'Neal does get healthy over the next month, do the Celtics really need him once Kendrick Perkins is healthy? What can we expect from J.O. the rest of the season?

A: The numbers suggest there's not going to be a heck of a lot of minutes to go around if Boston's entire front line of Perkins, Shaq, Jermaine O'Neal, Glen Davis and Semih Erden is healthy. But considering Shaq, Erden and Jermaine O'Neal have played virtually the entire season dinged up, it's hard to imagine Boston being completely healthy at any point the rest of the way.

So, yes, even if it's simply in an emergency role, the Celtics do need a healthy Jermaine O'Neal to eat minutes at some point this season and potentially in the playoffs. Ideally, Boston would love to keep those minutes manageable, especially into the postseason, but that's going to hinge on whether Perkins can get back to his pre-ACL injury level of play and how Shaq can hold up after logging elevated minutes to hold the fort during this Perkins-less stretch to start the season.

As for expectations with Jermaine O'Neal, it's probably safest to aim low. If he can simply stay healthy over the final two or three months of the season, that's a boon. And if he's able to log increased minutes on the nights Shaq or Perkins doesn't have it, that'd be a quality boost to Boston's frontcourt depth that would otherwise have to lean on a rookie like Erden instead.

The concern is that two months off didn't do enough to fix the swelling that Jermaine O'Neal is having in his ailing left knee and it's fair to wonder if another month (or even if it's stretched to six weeks) is enough to fix a knee injury that held up for only 10 games after a two-month break.

Q: As a team, Boston seems to be taking less 3-pointers this season. Did the Celtics make a concerted effort to limit trifectas this season?

A: It's ironic that the Celtics boast the NBA's soon-to-be all-time career leader in 3-point field goals (Ray Allen) and the defending 3-point shootout champion (Paul Pierce), yet the number of 3-pointers attempted this season has actually dipped dramatically, with Boston on pace to shoot 285 fewer triples than last season.

Rivers said Thursday his team hasn't changed its offensive philosophy.

"No, I don't emphasize not taking [3-pointers]," said Rivers. "I just want them to take good ones. I prefer the ball goes [inside] and comes out instead of us searching for [3-pointers]."

A healthy Garnett and the addition of a post presence like Shaq have revamped a Boston inside game that all but disappeared at the end of last season. Boston is averaging nearly seven more points per game in the paint than opponents this season, a whopping 44.1 points per contest from the painted area.

Low-post buckets are obviously higher-percentage shots and Boston's overall field goal percentage (a league-best 50.4 percent) is further proof of the renewed inside game. But the outside game is benefiting as well, with Boston shooting 38.7 percent beyond the arc (third best in the league).

"Yeah, [the inside-outside game has] returned, for sure," said Rivers. "Which is nice."

Oh, and for what it's worth. Wallace hoisted a whopping 290 3-pointers last season, which, maybe not surprisingly, would account for nearly the exact projected drop-off in Boston's 3-pointers this season. And his struggles beyond the arc might explain why Boston shot a mere 34.8 percent there last season.

Q: Will the Celtics make a move at the trade deadline?

A: The general philosophy is that, if you can make your team better, you explore all available options. But unlike past years when Boston might have had a glaring need (most noticeably for a backup ball-handler), I'm not sure there's a must-have type of player this season and Boston might be content to emerge from the late-February deadline with this 15-man roster intact.

But that doesn't mean Celtics president of basketball operations Danny Ainge can't gauge the market. But who's trade-able on this team? Well, there's a lot of one- and two-year deals at reasonable money, but players like Davis and Perkins might be the most attractive to other teams, and Boston is unlikely to want to move either.

One line of thinking suggests that a player like Nate Robinson could be dangled. If Boston is confident it can get by with Delonte West as the top backup at both guard positions, then the streaky Robinson, who has shown the ability to thrive in starter minutes, could be expendable. That said, Robinson's shooting ability off the pine might be of too great a value to explore moving.

What's Boston's biggest need at trade time? Provided players like West, Perkins and Jermaine O'Neal can get healthy around the All-Star break, Boston's biggest need might simply be another backup swingman to add some depth behind Pierce and Marquis Daniels.

Q: Why do the referees hate the Celtics so much? These whistles are out of control lately!

A: Sorry, conspiracy theorists (and Tommy Heinsohn loyalists), but the Celtics have been whistled for only 13 more personal fouls than opponents this season. The trouble lies in the fact that Boston has shot nearly 100 fewer free throws than opponents despite that similar number of infractions.

If this Boston team has one glaring flaw, it's an ability to get to the free throw line. The Celtics rank 27th in the league in total free throws attempted and a mere 24th in free throws per field goal attempt (.218 and the league average is .234; the Celtics give up .249 free throws to field goal attempts, ranking them in the bottom third of the league).

Free throws are free points and Boston would be well served to improve that number of attempts once the playoffs arrive. A continued focus on the inside game with Garnett, Shaq and a healthy Perkins could go a long way toward aiding that cause.

Just keep in mind that, in the NBA Finals last season, while everyone fixated on the rebounding disparity in Games 6 and 7, the free throw disparity was just as glaring. In fact, for the series, the Lakers attempted 51 more free throws (200 for LA; 149 for Boston) and all those extra points have a way of adding up.

Chris Forsberg is the Celtics reporter for ESPNBoston.com. Follow him on Twitter.