If the Hawks are forced to play Game 3 without forward Josh Smith, as expected, or even with him in a limited capacity, they’ll enter new territory this season. His 2,329 minutes rank ninth in the NBA this season, and he’s one of the 7.5 percent of players who played all 66 games of this lockout-shortened year.

While the Hawks listed Smith as day-to-day with a strained left knee, the inflammation as a result of patellar tendinitis leaves him doubtful for Friday night’s game in Boston, according to the Atlanta Journal-Constitution.

“It’s getting better and better each and every day,” said Smith via the AJC’s Michael Cunningham on Twitter. “I will see how it feels at shootaround [Friday]. “I have a high threshold for pain. If I feel like I can go a little bit I’m going to step out on the floor. At shootaround I will probably try to go a little bit harder than normal and see how it feels.”

Unlike the Celtics, who have become accustomed to playing without Ray Allen and a host of others all season long, the Hawks simply aren’t used to playing without Smith, Al Horford (torn pectoral) and Zaza Pachulia (strained left foot). And there are less obvious ramifications beyond that fact.

Smith’s usage rate (defined as the percentage of offensive possessions used by a player during his floor time) of 28.1 percent is the highest on the Hawks and ranks behind only Kevin Love, Dirk Nowitzki and DeMarcus Cousins among the league’s regular bigs. In other words, Atlanta’s offense runs through Smith.

He can score spotting up, posting up, in transition and (lord knows) in isolation. You name it, he does it. As Sports Illustrated’s Zach Lowe noted, “the Hawks have averaged about 104 points per 100 possessions when Smith plays, a borderline top-five mark, and a putrid 97 points per 100 possessions when he sits.” In their two playoff games, Atlanta has scored 90.6 points per 100 possessions with Smith, a stat that only stands to get worse.

Josh Smith's absence or ineffectiveness has serious repercussions on the Hawks' offense and defense. (AP)

Last season, in five games sans Smith, the Hawks finished 1-4, scoring 90 or fewer points in three of those contests. In the two previous seasons, they finished 7-7 without him, and that was the old Josh Smith. The new version enjoyed the most efficient offensive season of his career, even as the rest of the Atlanta offense has become progressively less efficient over the past three seasons.

Smith, Joe Johnson and Jeff Teague have scored 64 percent of Atlanta’s points in the series, and stopping two of them rather than three is a whole lot less difficult. Does Kirk Hinrich, Marvin Williams or a past-his-prime Tracy McGrady really strike fear into the Celtics hearts as a third option?

Defensively, Smith has been tasked with guarding either Brandon Bass or Kevin Garnett, both of whom are equally effective in the post and from mid-range. Smith’s athleticism has countered them well, as neither Bass nor Garnett has been particularly effective this series.

Without Smith, the Hawks are forced to counter with reserves Ivan Johnson and Jason Collins, one marginal and another woefully inept offensive player. While both strong defensively, neither matches the stature of Smith, who received five votes in the NBA Defensive Player of the Year voting.

The C’s offense hasn’t exactly been the “Showtime” Lakers of the 1980s, but the emergence of Garnett and/or Bass offensively can go a long way towards improving their 89.4 points per 100 possessions, especially with Rajon Rondo back in the lineup. Smith’s absence makes that task that much easier.

Statistics aside, the difference between Smith and his potential replacements can be gleaned over the past week from listening to Garnett, who rarely doles out praise to opposing players. Days before describing Ivan Johnson as a nobody, KG said, “Smith has played, to me, some of his best basketball.”

Respect from Garnett isn’t easily earned, and the fact Smith has says pretty much all you need to know.

(Have a question, concern or conception for the next Irish Coffee? Send a message to @brohrbach on Twitter.)