Not quite as advertised

Maybe the most frustrating aspect of how poorly the Boston Celtics have played defensively early in the 2014-15 season is how unexpected of an issue it was.

For all their warts (and losses), these Celtics were a team that hovered in the top half of the league in defensive rating for much of last season. Boston didn't quite address its glaring need for a rim protector this summer, but with the addition of Marcus Smart on the perimeter, along with changes to the team's defensive strategies to accentuate their strengths, there was reason to believe a player like former All-Defense member Avery Bradley when he said before the season that Boston had potential to be a top-10 defense.

And when the Celtics emerged from the preseason with the league's top-rated defense, it only seemed like confirmation that Boston's progress this season would be dictated by that side of the ball.

Nine games into the new campaign, the Celtics rank No. 27 in defensive rating, allowing a staggering 109.4 points per 100 possessions. Everything the Celtics are doing well -- particularly on the offensive side of the ball -- has been masked by defensive lapses that have routinely contributed to close games slipping away. And it has been Boston's poor defensive play that has prevented it from making progress.

As Stevens noted before the team practiced on Tuesday afternoon, "We scored 114 points against Phoenix and 121 against Cleveland -- that's enough. We gotta shore up the other end of the floor."

It's the defensive breakdowns that are keeping Stevens up at night. The Celtics have shown an ability to be a quality defense in small sequences, but have routinely given up 30-point quarters and left themselves no margin for error in crunch time when more experienced teams have made the necessary plays to emerge with wins.

Practices have centered on defense in recent days, and Tuesday's was no exception.

"It's frustrating, but it's the thing we're focused on," Stevens said. "We're going to go in [the film room] right after [media access] and we're going to watch and we're going to watch and we're going to watch and we're going to watch. We just all gotta get a little bit better. You don't have to rebuild the whole thing or recreate anything. We just have to be a little bit better in what we're trying to do."

If not for Boston's defensive woes, the narrative around the team at this point would center on a revitalized offense, a progression maybe even more startling than the defensive regression. The Celtics finished the 2013-14 season tied for 28th in offensive rating at an anemic 99.7 points per 100 possessions and were hard to watch at times last season when their offense sputtered. Even with a healthy Rajon Rondo, few expected the team's offensive numbers to spike this season.

But Boston currently sits sixth in the NBA with an offensive rating of 107.5. Only twice this season have the Celtics been held below triple-figures in scoring. In those other seven games, they're averaging 111.9 points per game.

All of which left Stevens cracking, "We're scoring like it's going out of style and the bottom line is we have to guard somebody to get what we want to do. And keep scoring. And it's a fine line, because I want to focus on both equally, but we have to mend the other end."

There's a suggestion that Boston's increased pace and all the energy being exerted on offense is limiting what the team can do defensively. Stevens dismisses that notion. There's virtually no correlation between pace on offense and how teams fare defensively. Ultimately, as Stevens notes, defense is a choice and one that a young Boston team hasn't been willing to put the necessary effort into to this point.

The absence of Smart, who sprained his ankle earlier this month, has certainly diminished Boston's perimeter defense, which has struggled at the point of attack recently. But Stevens is quick to point out the issues run deeper than the absence of a rookie.

The biggest issue Stevens sees is that Boston's success defensively is predicated on team defense. All five players must work together to create stops, and each piece of that puzzle has disappeared at different times. There's not one glaring area to fix, it's simply a need to get a full 48 minutes of effort out of each position.

"I think all five guys being on the same page each possession," captain Rajon Rondo said when asked about fixing the team's defense. "It may be four guys one possession, then one breaks down, it hurts our entire defense and teams capitalize on us. We have to continue to be on the same page. Especially in the crunch-time moments of the game."

Now, Boston is scoring with speed -- in fact that's part of the reason that unit has gotten a boost this season. According to the league's player tracking data, the Celtics own the second-lowest time of possession per game (17.6 minutes, only .1 minute more than the Denver Nuggets). That does mean Boston is playing defense longer -- but only because its goal is to force teams deep into the clock.

"It was interesting because I thought we kind of had a reputation at Butler of slowing things down," Stevens said. "And, our best teams, it was just because we were better defensively for longer periods of time. We usually shot it a lot quicker than [the opponents] did. I think there's a little bit of a myth to that. You have to be you on offense. Defensively, you have to set your defense so that you can help slow them down."

Stevens has implored his team to sprint back on defense, not only to eliminate transition opportunities but to simply get set and force opponents into playing against five set defenders. Sometimes that hasn't even been enough for Boston to generate stops.

For these rebuilding Celtics, the margin of error is simply much lower than for most squads, and that puts an increased premium on avoiding the lulls that have repeatedly sank them this season.

The bottom line is they must get better defensively for 48 minutes per game.

"It's a tough balance because we've got some guys that are in great position, but are not playing quite assertive enough," Stevens said. "And we have some guys that are not in as good of position, that are pretty assertive. I think at the end of the day is we chart every single play that every single person is in and we know exactly how many controllable errors you make. And we've got to get better at not making those controllable errors."