(Editor’s note: I’ll be out of the office (aka my parents’ basement) most of today, so this will be the one post for a while. My apologies.)

Shortly after Achilles was born, according to Greek mythology, his mother dunked him in the Styx River. Not to drown him, no, nor to teach him how to swim, but to make him invincible.

The river, which formed the boundary between Earth and the underworld, held certain powers, special powers that could make someone invulnerable. If Rajon Rondo had been dropped into the water, for example, I imagine he would have instantly become a deadly shooter. If Glen Davis had been dropped into the water, I imagine he would have started shooting better shots, rebounding at a rate a center could be proud of, and his body, I assume, would have become svelte. But when Achilles was dipped into the water, his mother needed to hold him somewhere. She grabbed him by the heel and submerged him in the river. Because her hand covered the heel, it was Achilles’ one body part to remain vulnerable.

The Boston Celtics have more flaws than Achilles did, indeed. They’re old and somewhat slow. They treat the regular season like Peter Gibbons in Office Space treats his job. If Jermaine O’Neal falls back to earth, they will be devoid of a true interior presence. And their bench, for whatever reason, has not performed despite having more talent than most NBA second units. Still, you get the feeling that Boston’s metaphorical mother, when she dropped them into the Styx Rivers, held them by the rebounds.

The Celtics finished 19th in the NBA in rebounding rate this year, tied with the Toronto Raptors and three spots below the Houston Rockets, who start 6-6 Chuck Hayes at center. The Celtics finished 9th in defensive rebounding, but dead last in offensive rebounds. We all remember last season (though we would love to forget), when Boston’s glass-cleaning woes manifested themselves at the worst possible time (in case you were wondering, I just jumped underneath a moving car).

Tuesday provided a painful reminder that Boston’s rebounding remains an issue. Despite missing the injured Amare Stoudemire, despite relying almost solely on Ronny Turiaf and Jared Jeffries (!) to protect the paint, New York handed Boston a 53-37 margin on the glass (including 20 New York offensive boards). After seeing his team get slapped around by the NBA’s 28th best rebounding unit, Doc Rivers decided to lead yesterday’s film session with 17 clips of rebounding (or, I would assume, the lack thereof). (ESPN Boston)

“We’re in help [defense] and we’re really not doing anything,” Rivers said in breaking down Boston’s rebounding struggles. “We’re kinda helping, but we’re not trapping. And when the shots go up, we just turn [toward] the glass. That means the guy that was helping, there’s nobody on his guy’s body.

“We showed that. That was our first 17 clips today. So, hopefully we’ve shown you can help, but you gotta recover back to the body because they’re sending all five guys to the glass. And they’re not even trying to get some rebounds; they’re just trying to keep the ball alive as long as possible. They feel they have a speed advantage, and it’s the old football adage: If you can knock the ball loose, the quicker guy gets the ball. The Jimmy Johnson rule — they’re doing that.”

After beginning the playoffs with two straight wins, the Celtics hardly seem content. While the Knicks followed Game 2 with comments like “that was fun,” “it’s not disappointing,” “you’re proud of your effort,” “[we] played great,” and “we’re doing great,” the Celtics could not hide their disappointment. Never mind that they won two straight. Never mind that both wins were scintillating. Never mind that the Celtics showed moments of greatness and the clutch hand of a team that has done this many times before. The Celtics aren’t in the playoffs to get past the first round. No offense to the Knicks, who have played admirably, but the two teams have very different aspirations. (Boston Herald)

“That means we’ve raised the bar on who we are,” coach Doc Rivers said after yesterday’s video session. “That’s a good thing, when you think about it. You’ve won two games, and the team that has won, the talk is they have to play better. The team that lost is like, ‘Wow, we did a great job.’ ”

Ray Allen says the Celtics’ deficiencies are staring them in the face. It’s easy to realize you need to improve when one of the league’s worst rebounding teams takes a 2×4 to your head; when Carmelo Anthony and four D-Leaguers push you to the verge of defeat; when the bench has been visibly non-existent and the starters far from perfect.

“We need one [dominating effort],” Glen Davis told ESPN. “We need one, ASAP. The thing about it, we haven’t played our best. It’s just like, this team playing at our best is hard to beat. When we put 48 minutes together, we’ll be alright.”

They shouldn’t need to put 48 minutes together to defeat the Knicks. But the playoffs won’t end after round one, the Celtics know, and they will get progressively more difficult. With that in mind, the Celtics will not be satisfied by mere wins. Instead, they’ll look to continue strengthening their heels. Achilles, mostly impenetrable, met his death because of  one vulnerability. The Celtics would like to avoid a similar fate.