Avery Bradley, Andre Miller, Kenneth FariedThe good news for the Celtics is, now they can make that trade for Chris Paul.

This is a trade proposal that honestly has been raised to me by fans on Twitter more than once since Rajon Rondo‘s season-ending knee injury, as though the only thing standing in the way of Paul coming to Boston was the Celtics’ refusal to take him off the Clippers’ hands. Curiously, more than two weeks after Rondo torn the anterior cruciate ligament in his right knee against Atlanta, the Celtics still have not pulled the trigger on this trade for the all-world point guard. Celtics president of basketball operations Danny Ainge must really be sleeping on the job.

In truth, the Celtics’ options for finding backcourt depth are limited even if they lower their standards from the elite tier Paul inhabits. Coach Doc Rivers realizes this, which is partly why he looked so distraught on Monday when reserve guard Leandro Barbosa went down in the third quarter with a left knee injury. In addition to basic concern for his player, Rivers knows the Celtics do not have many places to turn for guard help. It looks increasingly likely that Barbosa has torn his left ACL, which would give him and Rondo a matching set.

There are two players, familiar to Celtics fans, that are immediately available in the D-League. The first is Delonte West, who signed a minor league contract with the Texas Legends in spite of the understanding that the parent club in Dallas would never, ever extend him an NBA invitation. The other is 2012 Celtics second-round draft pick Kris Joseph, who has had a whirlwind few weeks. Joseph has been released by the Celtics, signed by Boston’s D-League affiliate in Maine and traded to Sprinfield, Mass., but he technically remains available for any team to sign. (Any player in the D-League who is not on an NBA roster can sign with an NBA team at any time.)

Still, if West could help an NBA team right now, chances are he would be on one already. And Joseph, who possesses some promising skills, is unlikely to offer much help this season.

The trade market is always a fun topic of conversation, but the Celtics’ dwindling numbers creates a sort of Catch-22. They need to make a move to bolster their roster, which consisted of only 11 healthy bodies before Barbosa’s injury, yet because they have so few healthy players, it is difficult for them to make an even-sided deal. This is not an opportune time to make a move, either — many teams are holding tight for the next week or so to see what happens in the run-up to the trade deadline. Even if the Celtics can work out a significant deal at the Feb. 21 deadline, that still leaves Rivers scrambling to patch together a rotation in the next nine days.

The NBA has made several changes in the last few years to minimize the chances of a team getting into the Celtics’ situation. Ironically, that may have left the Celtics with fewer options than they might have had 10 years ago. Rosters have expanded to 15 players from 12, creating extra spots for teams to stuff marginal NBA talent and, presumably, prevent a team like the Celtics from running out of players. Yet whereas those 90 fringe players — guys like Mike James and John Lucas III — would have once floated around the Continental Basketball Association or international game, they are now warming spots on NBA benches or even muscling their way into the rotation.

For a quick fix, the Celtics can bring up Shelvin Mack, a capable Butler product who has already played 11 games this season with the Wizards and Sixers. Mack, a 35-percent shooter from 3-point territory in college, has yet to see his accuracy translate to the pros, but that may be blamed on a shortage of opportunities. He has taken a total of 262 shots in his NBA career, an average of less than four per game. Mack is familiar with Boston’s system from spending the bulk of the season with the Celtics’ D-League affiliate.

The Celtics are indeed in a tight spot if Barbosa’s injury turns out to be as bad as it is feared. “Nobody said this would be easy,” Rivers likes to say, but nobody could have foreseen it being this difficult, either.

Have a question for Ben Watanabe? Send it to him via Twitter at @BenjeeBallgame or send it here.